# Rifle Action Truing



## thestelster (Feb 7, 2022)

Yesterday I machined 10 flutes onto a barrel.  Today we start the action and bolt truing.  To achieve maximum accuracy in a rifle, all the surfaces which make contact with the barrel have to be true.  The internal action threads, the action face, the recess where the bolt lugs lock into, all have to be concentric to the bore of the action where the bolt slides.  They seldom are.  So first we have to put the action into the lathe so we can do the work.


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## thestelster (Feb 7, 2022)

I purchased a number of 3/4" OD, 1/2" ID hardened bushings and using a mandrel, between centres on the lathe, turned them down to a number of different OD's.  The bushings get positioned in the action, front and rear.  The 1/2" dia. 12" long carbide rod goes through the bushings and sticks out past the action face.  Then using a dial indicator you go back and forth zeroing front and rear using the spiders' 8 bolts.  The spacing is 4".  This takes a while!  Once everything is is running true, pull out the rod, and now we can now start machining the required areas.


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## thestelster (Feb 7, 2022)

Once the locking lug recess, and action face is trued up, its time to chase the threads.  If you thought cutting threads is tricky.  Try doing internal, and virtually completely blind because the tools and holder and post is in the way.  I am not cutting new threads.  Just going deeper to get rid of any inconsistencies, which there are plenty, not concentric and not round!  So we have to pick up the existing thread.  Start the lathe, in slow, making sure that the cutter will not touch any part of the thread, engage the half nuts.  As the cutter just enters switch off the lathe but don't disengage the half nuts.  Now move the cross slide towards you, and with the compound (oh, which is parallel to the lathe axis) move the compound forward or back 0.001" at a time, and moving the cross slide towards you until you feel it bottom.  Keep an eye on the dial number.  You're at the bottom of the thread, when the cross slide is closest to you.   Put your dials to zero.  You can try that procedure a couple times  but take note, that if the threads are oval or not concentric, you'll get different results depending on where the lathe stopped, so don't worry about it too much.  Now you have to worry about the length of the treaded section.  I set up the dial indicator on the carriage stop.  I move the cutter in to the point that I want to end the thread.  Then move the carriage stop so that the dial indicator compress 1 full turn, lock the carriage stop and zero the dial.  Don't use a hard stop.  So what will happen, is that as the cutter is moving into the action, the carriage will touch the indicator probe.  You now have one full sweep of the needle to disengage the half nuts and move the cross slide away. This happens pretty quick, so you need to practice at a different section of the lathe.  When you're ready to go.  The compound is at zero, and we said that the bottom of the thread is zero, but start at say 5, or 10 on the dial.  With every pass, move the cross slide towards you 0.002". You will keep going until you've cleaned up all the threads.  You will hear when its cutting and not cutting, and when go to start another pass, examine it.  There is more information I need to mention, ie. Thread root flat and crest flat.


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## ShawnR (Feb 7, 2022)

Wow!


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## PeterT (Feb 7, 2022)

Nice. What is the cream colored stuff on the ends of cap screws? Is the threading tool a Vardex? What size thread are you cutting? 
That's a lot of coordination to get exactly right within 1 dial sweep at the end of the dark tunnel, bravo.


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## thestelster (Feb 7, 2022)

PeterT said:


> Nice. What is the cream colored stuff on the ends of cap screws? Is the threading tool a Vardex? What size thread are you cutting?
> That's a lot of coordination to get exactly right within 1 dial sweep at the end of the dark tunnel, bravo.


Hi Peter, that is just thick grease.  The grease allows the brass pads to stick to the cap screws while I'm positioning the action in the spyder.  The threading tool is a Sandvik.  The Remington Model 700 action uses 1.062" x 16tpi.  After single point cutting these threads, the new dimensions are 1.099" x 16tpi.  This is the new dimensions I have to machine the barrel to fit.  So, obviously, the old barrel would be loose as a goose in this action.


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## 6.5 Fan (Feb 8, 2022)

For sure setup time on jobs like this is longer than the actual work.


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## thestelster (Feb 8, 2022)

PeterT said:


> Nice. What is the cream colored stuff on the ends of cap screws? Is the threading tool a Vardex? What size thread are you cutting?
> That's a lot of coordination to get exactly right within 1 dial sweep at the end of the dark tunnel, bravo.


I occasionally have to do that with metric threads, so you can't disengage the half-nuts.  Adjectives describing that:  trepidation; fear; worry; and hopefully never remorse.  Though I have changed it up last year to run in reverse on the back side.  But you still can't disengage the half nuts.


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## Degen (Apr 2, 2022)

Nice.  Gotta read through the entire thread, much to learn in these posts.


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## Goldxxx (May 9, 2022)

I never had a lathe that was large enough to work on rifles or barrels until I bought my South Bend.  The work holder that you machined for the action, would it be considered a spider or just a work holding jig. It’s genius. I’m on a learning curve. I guess everything can’t always be held in a 3 or 4 jaw or faceplate.


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## Goldxxx (May 9, 2022)

If you have the room they are ideal for moving heavy things from a utility trailer. If it was a portable unit that I can be taken apart and stored, it would come in handy. Wish I had a gantry when I moved my Brother in Laws fireproof file safe.
 The pictures below is the homemade gantry that was used to deliver my lathe. Thanks again Kevin.


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## thestelster (May 10, 2022)

Goldxxx said:


> I never had a lathe that was large enough to work on rifles or barrels until I bought my South Bend.  The work holder that you machined for the action, would it be considered a spider or just a work holding jig. It’s genius. I’m on a learning curve. I guess everything can’t always be held in a 3 or 4 jaw or faceplate.


Yes, its called a spider, I think it goes by some other names as well. And yes, it is quite ingenious.  Solves a lot of alignment issues.


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## Susquatch (May 10, 2022)

Goldxxx said:


> I never had a lathe that was large enough to work on rifles or barrels until I bought my South Bend.  The work holder that you machined for the action, would it be considered a spider or just a work holding jig. It’s genius. I’m on a learning curve. I guess everything can’t always be held in a 3 or 4 jaw or faceplate.



Some call it a spider, some call it a double spider, and others call it a double cats eye. Mine is a triple.

It's actually easy to hold an action in a 3 or 4 jaw. But holding is not the problem. The problem as @thestelster explains, is positioning the internal raceway of the action across its entire length to be concentric with the rotating axis of the spindle. Only when it is fully concentric end to end can it be machining such that the threads, lugs, and face are all square and true to the rest of the final assembly.

If you think that is amazing, wait until you see how he does the chambering!


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## Goldxxx (May 10, 2022)

Thestelster, I apologize for post /picture and comment #11. I don’t know why but I tried to post this on another thread about Gantry cranes and somehow it ended up on your thread. I’m still fairly new to this website. I didn’t want to come across like I’m trying to hijack your thread. 
 I’m just “that Guy” sometimes that accounts the “reply all “ button


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## Susquatch (May 10, 2022)

Goldxxx said:


> Thestelster, I apologize for post /picture and comment #11. I don’t know why but I tried to post this on another thread about Gantry cranes and somehow it ended up on your thread. I’m still fairly new to this website. I didn’t want to come across like I’m trying to hijack your thread.
> I’m just “that Guy” sometimes that accounts the “reply all “ button



No worries, I think we all figured that out!


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## Degen (May 15, 2022)

Waiting for the chambering.

 I'm going to sign this......

Old enough to know a lot, learned enough that I still need to learn even more.


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## thestelster (May 15, 2022)

Sorry Degen, that one is already finished and gone.   I have to do a couple more rebarrel jobs soon, so I will post how I chamber.


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## Chicken lights (May 15, 2022)

I have a question about mounting a barrel to a receiver, but I only know enough to be dangerous. 

If I’m correct in how I understand this- the receiver is slightly tapered where the barrel registers. There are shims that go between the receiver and the barrel 

So the goal is to get the shim pack the correct measurement before tightening the barrel nut 

Too little of shims, results in barrel damage, too many shims, too loose of a barrel and not seated correctly 

Am I sort of on the right track, on how I understand things?


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## thestelster (May 15, 2022)

Chicken lights said:


> I have a question about mounting a barrel to a receiver, but I only know enough to be dangerous.
> 
> If I’m correct in how I understand this- the receiver is slightly tapered where the barrel registers. There are shims that go between the receiver and the barrel
> 
> ...


Hi @Chicken lights ,  on virtually all rifles that have their barrels threaded on, there is no tapered thread section, and there are no shims.  There are only a couple of rifles that I know of that have some sort of adjustment for headspace.  1, is the Lee Enfield which have several bolt heads to accommodate headspace variances through wear.  2.  Savage 110 series rifles which have a collar which you would "clock" to get the proper headspace.  (I'm sure there are other rifles with replaceable bolt heads which you might be able to get plus sizes.)  (Maybe military rifles as well, but I am not versed on those firearms.)   All the others, Remington, Winchester, Browning, Sako, Tikka, Weatherby, Mauser, Springfield, P17 & P14 Enfield, etc.,  you need to measure from the action face to the bolt face.  This distance must them match up with the distance from the barrel face (where it contacts the action), to the "go" gauge base when inserted into the chamber, (minus app. 0.002" for crush factor).  It's difficult to explain without pictures.  I will provide in the near future.


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## Chicken lights (May 16, 2022)

thestelster said:


> Hi @Chicken lights ,  on virtually all rifles that have their barrels threaded on, there is no tapered thread section, and there are no shims.  There are only a couple of rifles that I know of that have some sort of adjustment for headspace.  1, is the Lee Enfield which have several bolt heads to accommodate headspace variances through wear.  2.  Savage 110 series rifles which have a collar which you would "clock" to get the proper headspace.  (I'm sure there are other rifles with replaceable bolt heads which you might be able to get plus sizes.)  (Maybe military rifles as well, but I am not versed on those firearms.)   All the others, Remington, Winchester, Browning, Sako, Tikka, Weatherby, Mauser, Springfield, P17 & P14 Enfield, etc.,  you need to measure from the action face to the bolt face.  This distance must them match up with the distance from the barrel face (where it contacts the action), to the "go" gauge base when inserted into the chamber, (minus app. 0.002" for crush factor).  It's difficult to explain without pictures.  I will provide in the near future.


I’ll wait patiently for pictures, no rush 

So it’s possibly a “headspace” issue? I was warned it’s a one shot approach to get right, or you can ruin parts. The barrel isn’t threaded where it mounts to the receiver, the barrel nut attaches the barrel to the receiver


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## thestelster (May 16, 2022)

Chicken lights said:


> I’ll wait patiently for pictures, no rush
> 
> So it’s possibly a “headspace” issue? I was warned it’s a one shot approach to get right, or you can ruin parts. The barrel isn’t threaded where it mounts to the receiver, the barrel nut attaches the barrel to the receiver


@Chicken lights which firearm do you have, and what issues are you having?


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## Chicken lights (May 16, 2022)

thestelster said:


> @Chicken lights which firearm do you have, and what issues are you having?


PM sent


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## Susquatch (May 16, 2022)

Chicken lights said:


> I have a question about mounting a barrel to a receiver, but I only know enough to be dangerous.
> 
> If I’m correct in how I understand this- the receiver is slightly tapered where the barrel registers. There are shims that go between the receiver and the barrel
> 
> ...





Chicken lights said:


> So it’s possibly a “headspace” issue? I was warned it’s a one shot approach to get right, or you can ruin parts. The barrel isn’t threaded where it mounts to the receiver, the barrel nut attaches the barrel to the receiver



Yes, it's all about headspace. 

I agree with what @thestelster said.

Let me add that I think you are specifically talking about the Savage Barrel Nut but mixing in information you have heard about shouldered barrel designs (Remington, Winchester, etc). They are NOT the same. But the end result is. 

With the savage, it's definitely not a one shot thing. But even the others are not one shot efforts. It's easy to test fit till you get it right. 

A yahoo with a pipe wrench is a whole nuther matter. 

The part between the barrel and receiver is called a recoil lug. It is not a shim. It transfers recoil forces from the barrelled action to the stock.

They do sell recoil lugs in different thicknesses that can be used to change the head spacing but that isn't generally the way to do it. Normally, the chamber is cut to the correct headspace when it is reamed. Sometimes with prechambered barrels, you can also cut the barrel shoulder a bit to accomplish the same thing with minimum machining. But again, this is not the preferred approach it's only done to facilitate using pre-fit barrels.

This might be one of those things best explained on the phone or hands on during a visit. A visit like that would make it all obvious.


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## Chicken lights (May 16, 2022)

Susquatch said:


> Yes, it's all about headspace.
> 
> I agree with what @thestelster said.
> 
> ...


I’ll send a pic once I’m near the shop again. I’m not going down your way for a few weeks unfortunately


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## Susquatch (May 16, 2022)

Chicken lights said:


> I’ll send a pic once I’m near the shop again. I’m not going down your way for a few weeks unfortunately



OK, no problem. 

I'm not moving any time soon. A visit whenever you can make it will be fun!


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## thestelster (Jun 7, 2022)

Degen said:


> Waiting for the chambering.
> 
> I'm going to sign this......
> 
> Old enough to know a lot, learned enough that I still need to learn even more.


Here is one method of chambering rifle barrels.  There are a myriad of methods and I've used quite a number of them.  Use the method which is easiest for you and gives you the results you're after.  You might have to use different methods for different situations.  In this method the barrel is held in a spider and is centered with the 8 bolts, so that the bore of the barrel is running concentric and true with the axis of the lathe.  The reamer is positioned against a dead center in the tailstock.  The reamer is prevented from rotation by a tap wrench with one arm on the compound rest.  The depth of cut is controlled by the tailstock wheel, and measured with the dial indicator against an arm attached to the quill of the tail stock.  The reamer is held firmly against the dead centre with the left hand pulling rearward slightly.


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## thestelster (Jun 7, 2022)

Here is how I hold the reamer backwards against the center.


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## thestelster (Jun 8, 2022)

Oh, in case you're wondering about the blue glove.  I don't like wearing gloves unless I absolutely have to. It removes all the sensation of doing precise work and holding small parts, especially holding small parts during cleaning in the Varsol tank.  But considering I had carpal tunnel surgery last Thursday, and started working on Monday four days later....


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## Chip Maker (Jun 8, 2022)

Ouch!


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## Susquatch (Jun 8, 2022)

thestelster said:


> Oh, in case you're wondering about the blue glove.  I don't like wearing gloves unless I absolutely have to. It removes all the sensation of doing precise work and holding small parts, especially holding small parts during cleaning in the Varsol tank.  But considering I had carpal tunnel surgery last Thursday, and started working on Monday four days later....



And you are holding a Reamer back with that hand..... 

Shouldn't you be in the house milking that for sympathy with your SWMBO?


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## thestelster (Jun 8, 2022)

Susquatch said:


> And you are holding a Reamer back with that hand.....
> 
> Shouldn't you be in the house milking that for sympathy with your SWMBO?


SWMBO?  She wanted me to take it easy, but I can't sit around if there are things to do.  In fact, I was on my hands and knees cleaning and scrubbing up the whole bathroom the day after surgery.


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## Susquatch (Jun 8, 2022)

thestelster said:


> SWMBO?  She wanted me to take it easy, but I can't sit around if there are things to do.  In fact, I was on my hands and knees cleaning and scrubbing up the whole bathroom the day after surgery.



I wonder what your surgeon would have to say about that..... LOL!


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## thestelster (Jun 8, 2022)

Susquatch said:


> I wonder what your surgeon would have to say about that..... LOL!


Yeah, they usually just shake their heads.  Especially when I did a half-ironman triathlon a year and a half after my hip replacement!


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## Chicken lights (Jun 8, 2022)

Is threading a barrel muzzle a lathe operation or can you farm boy it with the  right die? 

(I’m sure you could point it on the lathe and finish it with a die, too)


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## Susquatch (Jun 8, 2022)

thestelster said:


> Yeah, they usually just shake their heads.  Especially when I did a half-ironman triathlon a year and a half after my hip replacement!



Something serious is the matter with me. 

I must be attracted to friends like you...... 

A buddy of mine for 60 years is scheduled to have a heart valve replaced. He was told to avoid any activity that raised his heart rate or blood pressure. He is busy ignoring those orders totally. 

You guys are both crazy..... 

But I like you anyway!


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## Susquatch (Jun 8, 2022)

Chicken lights said:


> Is threading a barrel muzzle a lathe operation or can you farm boy it with the  right die?
> 
> (I’m sure you could point it on the lathe and finish it with a die, too)



In my opinion it's a lathe job beginning to end. But a little different than chambering or crowning because the brake must look good on the outside AND have a concentric bore. This is not simple. It means setting up the bores of both barrel and brake concentric with the spindle for boring, threading, and shouldering and then cutting the OD of the brake to be concentric with the OD of the barrel. Remember that very few barrels have an OD and an ID that are actually concentric with each other.

However, I'd be willing to bet that there are a gazillion brakes out there that were done without a lathe with gaps at the interface, crooked alignment, and big fat diameters to hide the mismatch. And I doubt that most shooters care.


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## thestelster (Jun 8, 2022)

To get maximum recoil reduction from a muzzle brake, the bore of the muzzle brake should be between 0.015"-0.020" larger than bullet diameter.  That's 0.0075-0.010" per side clearance before the bullet hits the bore of the muzzle brake over 2-3" brake length.  That type of precision usually cannot be attained by a threading die.  Now, some off the shelf muzzle brakes, or even factory ones, have the bore of the muzzle brake considerably larger than what I stated earlier....for liability reasons.  But the larger the delta between bullet diameter and muzzle brake bore, the less effective it is, to the point where the brake  is purely cosmetic.


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## Chicken lights (Jun 8, 2022)

That makes sense, so it’s more than just cutting the threads, it’s about having the threads concentric to the centre of the barrel


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## thestelster (Jun 8, 2022)

Yes!


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## Susquatch (Jun 8, 2022)

thestelster said:


> To get maximum recoil reduction from a muzzle brake, the bore of the muzzle brake should be between 0.015"-0.020" larger than bullet diameter.  That's 0.0075-0.010" per side clearance before the bullet hits the bore of the muzzle brake over 2-3" brake length.  That type of precision usually cannot be attained by a threading die.  Now, some off the shelf muzzle brakes, or even factory ones, have the bore of the muzzle brake considerably larger than what I stated earlier....for liability reasons.  But the larger the delta between bullet diameter and muzzle brake bore, the less effective it is, to the point where the brake  is purely cosmetic.



Darn good point! 

I'd only add that full length concentricity and clearance also affects accuracy. Even though the brake doesn't touch the bullet, pressure differences affect the projectile and many claim it can introduce wobble and deteriorating accuracy.


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## historicalarms (Jun 8, 2022)

Susquatch said:


> Darn good point!
> 
> I'd only add that full length concentricity and clearance also affects accuracy. Even though the brake doesn't touch the bullet, pressure differences affect the projectile and many claim it can introduce wobble and deteriorating accuracy.


  I have never fired a gun with a "can" on it but see them used all the time now for even long range shots & every time i watch one I cant help but think as you do...that must effect accuracy big time.


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## thestelster (Jun 8, 2022)

Susquatch said:


> Darn good point!
> 
> I'd only add that full length concentricity and clearance also affects accuracy. Even though the brake doesn't touch the bullet, pressure differences affect the projectile and many claim it can introduce wobble and deteriorating accuracy.


I honestly don't know about pressure differences.  If we talk about a muzzle brake with equally spaced holes positioned 360° around the brake, would the gases not follow the path of least resistance and therefore impart minimal influence on the bullet?


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## historicalarms (Jun 8, 2022)

Chicken, I concur with both Susk & Theselster on lath cut accuracy for the treads & bore concentricity of the muzzle brake.

    Years ago when muzzle brakes were just an item on heave artillery and in their infancy for hand held sporting rifles, I and a buddy did an extensive testing regime on a home built muzzle brake for one of his custom rifles ( 32-378 Wby, a kicking, recoiling mule to say the least). This rifle was a two-shots-a-day proposition for me without a brake.
      We had access to his dad's lathe so many different designs were tried at very little cost other than our time...and purple-black armpit bruising on the failures.
    We tried 2-4-6 rows of holes, holes of different dia and holes of different angles to the bore direction...it was decided that 6 holes of a smaller dia at a very pronounced angle to the bore resulted in the most felt recoil reduction. We sprinkled fine dry sand on the shooting table and watched how the muzzle blast effected the dust...we could clean the table at the point of our shooting elbow with the design we thought worked the best...but man-o -man rearward directed the blast sure required excellent ear & eye protection.
     After the design was finalized we started fine tuning the reduction felt by changing bore dia. As Theselster states a tight bore to bullet dia is needed. We settled on .0025" clearance was when we felt the least recoil....that rifle, un checked probably produces 90-95 ft lb felt recoil with the load he uses but after all our testing that thing is as tame as a .243.
     Muzzle brakes can be a colossal waist of money & effort if not done properly.


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## Susquatch (Jun 8, 2022)

thestelster said:


> I honestly don't know about pressure differences.  If we talk about a muzzle brake with equally spaced holes positioned 360° around the brake, would the gases not follow the path of least resistance and therefore impart minimal influence on the bullet?



Since I have never actually used one myself (and never will) I can only relate the expertise of others whose shadows I am not worthy to walk in. 

The way I've heard it is that the pressure disappation itself isn't as important as the vibrations (pressure waves) that the ports introduce and that those waves are imbalanced by extremely small variations in clearance. 

I kinda look at it this way. Lots of shooters claim that the Crown doesn't matter. I'm here to say BS. Yet if we look at the Crown as a way to vent gases evenly and perfectly so as to avoid kicking the base of the projectile, it's a no brainer to me that something that reflects gas pressure waves back at the projectile has to be important too.


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## Susquatch (Jun 8, 2022)

historicalarms said:


> This rifle was a two-shots-a-day proposition for me without a brake.
> We had access to his dad's lathe so many different designs were tried at very little cost other than our time...and purple-black armpit



And this is why I do not own anything that big and don't need brakes.


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## historicalarms (Jun 8, 2022)

thestelster said:


> I honestly don't know about pressure differences.  If we talk about a muzzle brake with equally spaced holes positioned 360° around the brake, would the gases not follow the path of least resistance and therefore impart minimal influence on the bullet?


  Our testing soon showed you dont want holes full 360....the bottom holes will "jump" the bore before the slug has cleared the muzzle brake. It might sound very relevant to have an equal blast force for full circumference but the fact is that upwards movement of the rifle is the only direction it can move with no friction impediment when the shot is broke sideways & downward movement are all "friction slowed" by hand or bench contact.
    We notice more "target fliers" with holes under the bore than without so surmised (without any mechanical effort or devise to prove) that the muzzle could jump quick enough to sometimes affect the slug travel


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## Susquatch (Jun 8, 2022)

historicalarms said:


> We notice more "target fliers" with holes under the bore than without so surmised (without any mechanical effort or devise to prove) that the muzzle could jump quick enough to sometimes affect the slug travel



I surmise that it isn't so much the muzzle jump itself as much as the resulting pressure variations that caused this result. 

But we could debate all that till @6.5 Fan s cows come home. 

I think the bottom line here is that close attention to the detail that only a good lathe in good hands can provide is required to have any reasonable hope of success.


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## historicalarms (Jun 9, 2022)

Your right but i just looked outside & no cows yet...so..

   Not convinced pressure variance is at play here as equal distance hole spacing for 360 deg should have essentially an equal pressure at the exact same time for wherever the slug is in its travel through the brake. The bore was out beyond the table edge so back pressure between table & bore is non existent ( along with the surmising that the slug would have long excited the bore before the blast force returned from the table to bounce the barrel)  . 
     With no sophisticated testing equipment to be had we had to more or less theoretically remove each possible scenario until we were left with the one remaining possibility that we could not overrule, that being that the bore could not be directed downwards at all by the upwards direction of muzzle blast out of the top holes & sideways movement was slowed by front stock friction between it and the bench rest long enough for the slug to exit the bore. These and one other realization that happened convinced us...When we only had holes through the top and sides of the brake we had no more fliers.


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## Susquatch (Jun 9, 2022)

historicalarms said:


> Your right but i just looked outside & no cows yet...so..
> 
> Not convinced pressure variance is at play here as equal distance hole spacing for 360 deg should have essentially an equal pressure at the exact same time for wherever the slug is in its travel through the brake. The bore was out beyond the table edge so back pressure between table & bore is non existent ( along with the surmising that the slug would have long excited the bore before the blast force returned from the table to bounce the barrel)  .
> With no sophisticated testing equipment to be had we had to more or less theoretically remove each possible scenario until we were left with the one remaining possibility that we could not overrule, that being that the bore could not be directed downwards at all by the upwards direction of muzzle blast out of the top holes & sideways movement was slowed by front stock friction between it and the bench rest long enough for the slug to exit the bore. These and one other realization that happened convinced us...When we only had holes through the top and sides of the brake we had no more fliers.



Again, I'm just providing my thoughts on this for whatever they are worth to you. If that is zero, I take no offense. Sometimes we must accept the results we get whether or not we fully understand why. 

In trying to visualize my thinking on this, try not to think about combustion gases venting out of selected holes or symmetric holes. In fact, try not to think about gases venting at all. Instead try to think about this gas as though it were standing still but vibrating with entrained sound pressure waves. More or less the same concept as an AM radio signal carried by a radio frequency signal. In reality, the gases are moving and venting, but they also carry pressure waves within the gas that bounce around in there much much faster than the gases themselves. And because the gas is so highly compressed and dense, these waves travel through the combustion gases much much faster than the speed of sound and much much much faster than the speed of the gas itself. 

If you are familiar with the OBT (Optimum Barrel Time) theory of how accuracy nodes arise, you will understand that barrel vibrations caused by charge detonation travel up and down the barrel faster than the projectile does and that these vibrations (not the same as barrel whip) affect the projectile's internal ballistics. Mind you, despite its very widespread adoption, I don't buy the OBT theory in total. I think there is a lot more to it than that. But nonetheless, the principles are similar enough to be worthy of the comparison. 

I am only "suggesting" that these *density waves* (not the gas movement itself) that are inside the gases themselves reflecting off of various surfaces could cause various things to happen and that they could be both bad and good depending on their precise timing, direction, and consistency. 

All things being equal, I am a very firm believer in consistency  - everything and anything that could have an effect should be controlled as consistently as possible for the best results. Hence my position that the axis of the brake ID should be concentric to the axis of the bore. 

I totally understand and accept your findings about the brakes affect on the target results. This is quite similar to the difference between constrained and unconstrained recoil. The difference matters and your results show that. 

Anyway, it's just my thinking on the matter. You didn't seem to understand what I meant about the difference between gas pressure and pressure waves within the gas so I thought it might be worth an explanation.


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## Degen (Jun 9, 2022)

I'm going to chime in here the OBT has some merit, but more so with the harmonics of the barrel and vibrations introduced by the bullets motion (ands its related mechanisms).    If they are in phase they they amplify the problems of they are 180 degrees out of phase they cancel each other out.

These is some what controlled by length, shape diameter and so on.

Compensators on the other hand act in two fashions, the air passing through ahead of the bullet this starts recoil reduction and venting of gas behind the bullet.  If you look at well designed ones they actual have a little large "land" as the bullet finally exits to create mitigate the potential of off set thrust vectors as @Susquatch suggests.  Yes they do impart some potential variations but again as with well design barrels, well designed compensators do the same.  However for the best performance they must be integrated in the barrel design system.


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## Susquatch (Jun 9, 2022)

Degen said:


> I'm going to chime in here the OBT has some merit, but more so with the harmonics of the barrel and vibrations introduced by the bullets motion (ands its related mechanisms).    If they are in phase they they amplify the problems of they are 180 degrees out of phase they cancel each other out.
> 
> These is some what controlled by length, shape diameter and so on.
> 
> Compensators on the other hand act in two fashions, the air passing through ahead of the bullet this starts recoil reduction and venting of gas behind the bullet.  If you look at well designed ones they actual have a little large "land" as the bullet finally exits to create mitigate the potential of off set thrust vectors as @Susquatch suggests.  Yes they do impart some potential variations but again as with well design barrels, well designed compensators do the same.  However for the best performance they must be integrated in the barrel design system.



I just used OBT as an analogy to introduce the concept of vibrating pressure waves within the expanding gases. I didn't mean to imply that's what is directly going on here. 

In my mind it's too simplistic to think of the expanding gases as a single process with a relatively long time interval. I think it's important to remember that the gas column also contains very fast pressure waves that move much faster through the gases than the expanding gas column moves itself. I mentioned OBT only because these gas pressure waves are similar to the barrel ringing that travels back and forth the length of the barrel faster than the projectile does. 

Whether that really matters or not? I don't know. But I'd bet that it does.


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## Degen (Jun 9, 2022)

@Susquatch we are on the same page.

It does matter, with or without compensator.  These are call Standing Wave Ratios, the trick is to have them cancel each other out at the right time.

Think positive and negative nodes traveling in opposite directions, if the meet at the exit point when both are either same extreme, bad....when the meet when both at at the opposite side then excellent (with hands rubbing together ).

These and the barrel (and compensator) harmonics (among other things) are what determine your ultimate performance.

Creating a load that performs best does exactly that by playing with those items (yes I know you are better than it than I)


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## Chicken lights (Jun 9, 2022)

@thestelster was explaining some of the bullet dynamics and I think I just figured out a parallel, a football!! Think about it, how and where you grip it dictates the spiral, and depending on how long or short you’re throwing it, changes the angle of the throw. He was explaining the boolit spiral doesn’t slow down (much) yet the velocity does, and thats the same with a football, if you watch a long pass


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## Susquatch (Jun 9, 2022)

Degen said:


> @Susquatch we are on the same page.
> 
> It does matter, with or without compensator.  These are call Standing Wave Ratios, the trick is to have them cancel each other out at the right time.
> 
> ...



OK. I think so too.

I'm not so sure that a standing wave is an accurate description of what happens inside a brake with a plethora of excitation sources but that's a whole nuther conversation not worth having on the forum. Maybe beside a campfire someday. For the primary discussion I agree we are on the same page.


Chicken lights said:


> @thestelster was explaining some of the bullet dynamics and I think I just figured out a parallel, a football!! Think about it, how and where you grip it dictates the spiral, and depending on how long or short you’re throwing it, changes the angle of the throw. He was explaining the boolit spiral doesn’t slow down (much) yet the velocity does, and thats the same with a football, if you watch a long pass



Yes, its a very good parallel. And for many of the same reasons. It is a good place to start and I like it. You can build on that.


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## Chicken lights (Jun 9, 2022)

Susquatch said:


> OK. I think so too.
> 
> I'm not so sure that a standing wave is an accurate description of what happens inside a brake with a plethora of excitation sources but that's a whole nuther conversation not worth having on the forum. Maybe beside a campfire someday. For the primary discussion I agree we are on the same page.
> 
> ...


Boolit weight- it’s easier to keep a larger mass moving straight once you get it moving, but harder to get moving? 

I realize that’s not a yes/no question 

Easier to stabilize a heavier projectile? Heavier projectile harder to deflect? 

I’m guessing it’s all a trade off on what you’re trying to achieve


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## Susquatch (Jun 9, 2022)

Chicken lights said:


> Boolit weight- it’s easier to keep a larger mass moving straight once you get it moving, but harder to get moving?



yes,  -  and YES it is a yes no question LOL! 



Chicken lights said:


> Easier to stabilize a heavier projectile?



Depends on what you mean by easier. In general weight is not as important as length weight ratio - what is generally called sectional density. But even that isn't the total answer. There are calculators out there that can be used to estimate stability and some manufacturers publish ratings and recommended twists. 



Chicken lights said:


> Heavier projectile harder to deflect?



Generally Yes


Chicken lights said:


> I’m guessing it’s all a trade off on what you’re trying to achieve



Yes yes YES! There is no such thing as perfect in this game. Just better and worse for your goals.


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## Degen (Jun 10, 2022)

In term of these shock waves (vibrations), think of active noise cancellation used in some cars (or other applications), same base theory just method of application is different.  

(Remember the tune wt started by Browning on the barrel end which lets you dial in your barrel to you load vs making the load fit your barrel).

Believe it or not in a barrel doing this is significantly easier than in other forms as you have a controlled space to start with.


As to stability, this gets into some weird stuff.  It has to do with perceived rotational mass vs presented surface area vs drag vs a lot of other things.  The math gets beyond my realm very quickly.  The actual concepts are relatively simple however hit the right combination is the trick.


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## Chicken lights (Jun 10, 2022)

Susquatch said:


> yes,  -  and YES it is a yes no question LOL!
> 
> 
> 
> ...


I very briefly looked at Hornady’s boolit chart last night, holy crap there’s some math for you!

That’s too much for this driver right now,  I’ll follow along and ask the odd question but I’ve other things needing attention before winter prep


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## Degen (Jun 10, 2022)

Chicken lights said:


> I very briefly looked at Hornady’s boolit chart last night, holy crap there’s some math for you!
> 
> That’s too much for this driver right now,  I’ll follow along and ask the odd question but I’ve other things needing attention before winter prep


Yeap, so do what some of the old shooters do, change only one thing till you've exhausted the change for performance and forget the math.


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## Susquatch (Jun 10, 2022)

Chicken lights said:


> I very briefly looked at Hornady’s boolit chart last night, holy crap there’s some math for you!
> 
> That’s too much for this driver right now,  I’ll follow along and ask the odd question but I’ve other things needing attention before winter prep



As they say - different strokes for different folks. I love the math. But this is one sport with lots of room for every stroke there is. Just relax and enjoy the trip! 

When you are ready, I know lots of ways to describe the complicated math in simpler terms that work for everyone! 

Of course that will invite lots of the inevitable debate.... LOL!


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## 6.5 Fan (Jun 10, 2022)

My recommendation is get to the range and shoot and have fun doing it. If you learn some good information that is a bonus.


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## 6.5 Fan (Jun 10, 2022)

Also the cows won't be coming home till Oct.


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## historicalarms (Jun 10, 2022)

Well we kind'a "sideways" this thread a bit ....but damn its been interesting & informative.
    Chicken, your "football" concept is one of the oldest and most re-engineered concepts of barrel making & shooting since spiral rifling was first introduced into the quotient....the trial & errors of different rifling forms & twist rates have been re-engineered every time a new caliber is introduced and then again for every different bullet ever produced ( the "sectional density" thing that Susq mentioned) and we aint never gonna get all that rehashed in this liftime.


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## Susquatch (Jun 10, 2022)

historicalarms said:


> the trial & errors of different rifling forms & twist rates have been re-engineered every time a new caliber is introduced



I smell an absolutely wonderful discussion/debate/fight here about the black magic of the 6.5CM......  definitely a terrific hunt camp discussion! LOL!


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## Degen (Jun 10, 2022)

In terms of accuracy, most still need to learn to sight correctly along with a correct trigger pull, after that start blaming other things.


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## Tom O (Jun 10, 2022)

6.5 Fan said:


> Also the cows won't be coming home till Oct.


Curly‘s passed but you could use his brother and those City Slickers.


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## Chicken lights (Jun 10, 2022)

Degen said:


> In terms of accuracy, most still need to learn to sight correctly along with a correct trigger pull, after that start blaming other things.


Correct trigger pull seems to be another hot topic 

I’m open to learn but fear that’s opening another can of worms


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## Tom O (Jun 10, 2022)

Ever wonder why the trigger isn’t on a angle or be able to float a little side to side to compensate for the arc movement of the finger


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## 6.5 Fan (Jun 11, 2022)

Tom O you haven't shot a worn out cooey or you wouldn't ask about side to side trigger float.


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## Susquatch (Jun 11, 2022)

Tom O said:


> Ever wonder why the trigger isn’t on a angle or be able to float a little side to side to compensate for the arc movement of the finger



Don't know which model you mean, but can say that a trigger made by Trigger Tech in Canada will make you smile from ear to ear. They are expensive but totally worth every penny. The design is insensitive to side thrust - and darn near every other trigger curse I know of.


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## Susquatch (Jun 11, 2022)

6.5 Fan said:


> Tom O you haven't shot a worn out cooey or you wouldn't ask about side to side trigger float.



My very first two guns almost 70 years ago were Cooeys. They were horrid things but as a young boy I loved them. They also taught me some good habits that have lasted a lifetime.


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## thestelster (Jun 11, 2022)

Tom O said:


> Ever wonder why the trigger isn’t on a angle or be able to float a little side to side to compensate for the arc movement of the finger


Have a look at any Olympic Match Rifle, or target pistol by Anshutz, Hammerli, Walther, Feinwerkbau.


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## thestelster (Jun 11, 2022)

Jewell Triggers for Remington actions.


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## Susquatch (Jun 11, 2022)

thestelster said:


> Jewell Triggers for Remington actions.



I bet you have not tried Trigger Tech....... For obvious reasons, they started out with triggers for Remington. They must have a half dozen different ones now just for Remington. 

Almost all my old triggers are Jewell. All my new ones are Trigger Tech.


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## 6.5 Fan (Jun 11, 2022)

I have several Trigger Tech triggers on Rem actions, they are my go to unit.


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## historicalarms (Jun 12, 2022)

Holy man--- from turbulence to twist to triggers...all in one page... Ime going on 68 yrs old and aint got enough "lifetime" left in me to come close to covering 60 yrs of shooting & all the above--but you guys keep on I'll enjoy the ride as long as I can.


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## historicalarms (Jun 12, 2022)

Degen said:


> In terms of accuracy, most still need to learn to sight correctly along with a correct trigger pull, after that start blaming other things.


But I will agree with Degen wholeheartedly ,   without first conquering the human frailties of shooting, the very best-most expensive equipment in the world will not make a person a "shooter" of the first degree.


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## Susquatch (Jun 12, 2022)

historicalarms said:


> Holy man--- from turbulence to twist to triggers...all in one page... Ime going on 68 yrs old and aint got enough "lifetime" left in me to come close to covering 60 yrs of shooting & all the above--but you guys keep on I'll enjoy the ride as long as I can.



I agree with that! At mid 70s, the biggest risk is falling asleep in the middle of typing. 

The problem isn't really not being able to type long notes or even cover lots of ground. It's the width, length, and depth of the subject. 

Best to come over to chat and kick me when I doze off.


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## Susquatch (Jun 12, 2022)

historicalarms said:


> But I will agree with Degen wholeheartedly ,   without first conquering the human frailties of shooting, the very best-most expensive equipment in the world will not make a person a "shooter" of the first degree.



A game I like to play with the young shooters (old shooters are too stubborn) who claim I only shoot well because I have competition equipment is to load up 20 rounds, let them pick 10 rounds and give me the other 10, and then we both take turns to shoot 2 five shot groups. If they complain that the wind was in my favour, I'll do a round Robin with them for the last pair of groups.

There is no question that a nice bench rifle makes them a better shooter so I'll often repeat that with a hunting rifle to make it real for them. It's funny how much better they listen to advice after that. It's also amazing how quickly a young shooter improves when they are open to suggestions.


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## Chicken lights (Jun 12, 2022)

Susquatch said:


> A game I like to play with the young shooters (old shooters are too stubborn) who claim I only shoot well because I have competition equipment is to load up 20 rounds, let them pick 10 rounds and give me the other 10, and then we both take turns to shoot 2 five shot groups. If they complain that the wind was in my favour, I'll do a round Robin with them for the last pair of groups.
> 
> There is no question that a nice bench rifle makes them a better shooter so I'll often repeat that with a hunting rifle to make it real for them. It's funny how much better they listen to advice after that. It's also amazing how quickly a young shooter improves when they are open to suggestions.


I’m always open for suggestions, but the trick is knowing if the person giving advice is worth listening to. That’s in general, in my opinion, not just related to shooting. 

Then there’s the old buggers who yell at you to do it “properly” (their way) and will rap your knuckles if you don’t 

Luckily they nap a lot LOL


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## cuslog (Jun 12, 2022)

Degen said:


> In terms of accuracy, most still need to learn to sight correctly along with a correct trigger pull, after that start blaming other things.


I like to think of it as: "Drop the hammer without disturbing the sights" and then "follow through".
Seen quite a few people spend a fair chunk of $ trying to get better by buying high end equipment before they learned how to "drop the hammer without .....
Lots of us have been guilty of that though (myself included). Still forget sometimes


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## DPittman (Jun 12, 2022)

Chicken lights said:


> I’m always open for suggestions, but the trick is knowing if the person giving advice is worth listening to. That’s in general, in my opinion, not just related to shooting


Ain't that the truth.  Usually the most outspoken and quick to offer advice comes from those that are least qualified and/or very close minded to anything that deviates from "their" method.  And as you eluded to, it is often the same from shooting sports, to motorcycles, to sausage making, to beer making, etc, etc.


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## Chicken lights (Jun 12, 2022)

DPittman said:


> Ain't that the truth.  Usually the most outspoken and quick to offer advice comes from those that are least qualified and/or very close minded to anything that deviates from "their" method.  And as you eluded to, it is often the same from shooting sports, to motorcycles, to sausage making, to beer making, etc, etc.


Like you said, I think, usually, the people that quietly watch you perform a job, then quietly pull you aside later and offer some small advice, are the ones (usually) that can be relied on. 

The loud ones that talk all the time like @Susquatch are generally full of hot air 

(ducks for cover) 

(and totally kidding but hey why not poke the bear)


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## Susquatch (Jun 12, 2022)

Chicken lights said:


> I’m always open for suggestions, but the trick is knowing if the person giving advice is worth listening to. That’s in general, in my opinion, not just related to shooting.



That's the reason for shooting side by side groups with the young ones. Paper doesn't lie. When the dead dog is laying on the table, they are more willing to set their egos aside, let you rap their knuckles, and listen when you tell them that they are yanking, flinching, pushing, sitting different, rest is inconsistent, not squeezing the bag right, not following through, etc. etc


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## Degen (Jun 13, 2022)

cuslog said:


> I like to think of it as: "Drop the hammer without disturbing the sights" and then "follow through".
> Seen quite a few people spend a fair chunk of $ trying to get better by buying high end equipment before they learned how to "drop the hammer without .....
> Lots of us have been guilty of that though (myself included). Still forget sometimes


Yes, I was just putting it into the simplest terms possible.

Having always gone to the competitive side in anything that I do (this is a flaw I'm told by some ) and usually transition to the high end of whatever for equipment.  Though over the years to truly maximize the benefits of said top end equipment you NEED to master the simple basics, otherwise its a waste of money.

And in some cases the better equipment hinders learning.


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## Tom O (Jun 13, 2022)

Some people give good advice
some people try to verify their existence.


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## Chicken lights (Jun 21, 2022)

Susquatch said:


> That's the reason for shooting side by side groups with the young ones. Paper doesn't lie. When the dead dog is laying on the table, they are more willing to set their egos aside, let you rap their knuckles, and listen when you tell them that they are yanking, flinching, pushing, sitting different, rest is inconsistent, not squeezing the bag right, not following through, etc. etc


I’m gonna open a bag of worms-

Why are there umpteen million choices for boolit weight? I’m (slowly) learning that lighter boolits go faster/ heavier goes slower

Ok cool, but why 150 grain, 158 grain, 165 grain etc? 

Yes I also realize there are BT or HP or FMJ or on and on for choices for boolit design

Is there seriously a difference between a 150 grain projectile and a 158? 

Going from memory you said you use 165 for target and 168 for hunting (could be backwards)

The heck is the difference in such small weight?


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## DPittman (Jun 21, 2022)

Chicken lights said:


> I’m gonna open a bag of worms-
> 
> Why are there umpteen million choices for boolit weight? I’m (slowly) learning that lighter boolits go faster/ heavier goes slower
> 
> ...


Check out one of the many online ballistic calculators and play with the numbers a bit and you will see why there are so many choices, because they all perform a bit differently in different conditions.


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## Susquatch (Jun 21, 2022)

It


Chicken lights said:


> I’m gonna open a bag of worms-
> 
> Why are there umpteen million choices for boolit weight? I’m (slowly) learning that lighter boolits go faster/ heavier goes slower
> 
> ...



It's not a can of worms. Let's start at the end first.

Yes, you have it backward. 168 for target and 165 for hunting. As far as weight goes, they are virtually the same. But the 165 is a hunting design for controlled expansion and clean kills. The 168 is less than optimum for controlled expansion but has better consistency for target shooting. They may be roughly the same weight but they are totally different designs for totally different purposes.

OK, now for the bigger picture. Different weights even close to each other often have different profiles, different jacket designs, and different purposes. Light game heavy game, short range long range, etc etc. The barrel twist often sets limits on which weights will work, and many rifles are fussy. They will shoot one weight and design great but another not so great. Ya gotta find what works in your rifle for your intended purpose. Lots of brands to play with too.


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## Susquatch (Jun 21, 2022)

@Chicken lights - before you ask, yes - it's the same with powders and primers and even brass. Might be close but still different enough that ya gotta find what works for you.


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## Chicken lights (Jun 21, 2022)

DPittman said:


> Check out one of the many online ballistic calculators and play with the numbers a bit and you will see why there are so many choices, because they all perform a bit differently in different conditions.


I get that - but you can change ballistic characteristics in the same cartridge, with projectile weight and powder manufacturer alone 

I believe


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## Susquatch (Jun 21, 2022)

Chicken lights said:


> I get that - but you can change ballistic characteristics in the same cartridge, with projectile weight and powder manufacturer alone
> 
> I believe



Yup, you are right about that. 

Assuming you already have a rifle and cartridge, start with what is your purpose. Then set yourself some limits to play with that meet that purpose. Then look at twist limits, oal limits, and range limits and then pick a few bullets, some powder and and some loads that fit that profile and load some up (start low and work up) till you find what works for you. Or call me and we can talk.


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## Chicken lights (Jun 21, 2022)

Susquatch said:


> Yup, you are right about that.
> 
> Assuming you already have a rifle and cartridge, start with what is your purpose. Then set yourself some limits to play with that meet that purpose. Then look at twist limits, oal limits, and range limits and then pick a few bullets, some powder and and some loads that fit that profile and load some up (start low and work up) till you find what works for you. Or call me and we can talk.


I agree, I need some help loading as a beginner but have goals 

My immediate problems is that I have friends that reload, but don’t reload “X” cartridges, well that and I need to actually be home more than a half day 

I know you’ve been busy with farming and family stuff so haven’t asked for anything, I know you’d be welcome to help out normally


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## Susquatch (Jun 21, 2022)

Chicken lights said:


> I agree, I need some help loading as a beginner but have goals
> 
> My immediate problems is that I have friends that reload, but don’t reload “X” cartridges, well that and I need to actually be home more than a half day
> 
> I know you’ve been busy with farming and family stuff so haven’t asked for anything, I know you’d be welcome to help out normally



My crops are in, my taxes are ready to file, my mom is ok for now. No doctors appointments for a while. Funeral Home is too busy for me. Time to play now.


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## Chicken lights (Jun 21, 2022)

Susquatch said:


> My crops are in, my taxes are ready to file, my mom is ok for now. No doctors appointments for a while. Funeral Home is too busy for me. Time to play now.


More importantly, the wife is doing well?

The backbone to the operation, however quiet, plays the largest part


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## 6.5 Fan (Jun 22, 2022)

Jeeez, Sasquatch's wife is run off her feet keeping him on the straight and narrow.


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## Susquatch (Jun 22, 2022)

Chicken lights said:


> More importantly, the wife is doing well?
> 
> The backbone to the operation, however quiet, plays the largest part





6.5 Fan said:


> Jeeez, Sasquatch's wife is run off her feet keeping him on the straight and narrow.



@Chicken lights is totally right about her, and @6.5 Fan has no slightest clue. 

My bride is a saint. She is immortal, invincible, ageless, gorgeous, charming, never wrong, and she has the memory of a steel trap - especially for things I did wrong 50 years ago. She is also the perfect mother, grandmother and great grandmother. Her cooking and housekeeping are nothing less than amazing - actually embarrassing when contrasted with my own abilities in those arenas.  She does have a few faults though: she has no sense of direction, severe lack of respect for tools and their proper use, and a hyperactive supply of estrogen.


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## Degen (Jun 22, 2022)

Susquatch said:


> @Chicken lights is totally right about her, and @6.5 Fan has no slightest clue.
> 
> My bride is a saint. She is immortal, invincible, ageless, gorgeous, charming, never wrong, and she has the memory of a steel trap - especially for things I did wrong 50 years ago. She is also the perfect mother, grandmother and great grandmother. Her cooking and housekeeping are nothing less than amazing - actually embarrassing when contrasted with my own abilities in those arenas.  She does have a few faults though: she has no sense of direction, severe lack of respect for tools and their proper use, and a hyperactive supply of estrogen.


Danger Will Robertson , Danger, never ever point out the flaws, this will only add to the steel trap of a mind.


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## Susquatch (Jun 22, 2022)

Degen said:


> Danger Will Robertson , Danger, never ever point out the flaws, this will only add to the steel trap of a mind.



No worries. After 55 years of being together I've got it all figured out. She keeps me alive to keep her estrogen under control.

For now I'm ok, but someday soon I will need help. With my luck that will be the same day Canada stops the sale of Viagra. The steel trap will close later that same day and then I'm a dead man.

For now, I enjoy playing with fire!


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## Chicken lights (Jul 20, 2022)

Back to muzzle devices- can you trust factory threads on a barrel to have concentric ID to OD parameters? or as @Susquatch pointed out would the factory care about such tolerances?


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## thestelster (Jul 21, 2022)

Chicken lights said:


> Back to muzzle devices- can you trust factory threads on a barrel to have concentric ID to OD parameters? or as @Susquatch pointed out would the factory care about such tolerances?


Trust is a dangerous game!  I'm sure the concentricity is within some tolerance...but what that is, who can say until you actually measure.  And the manufacturer's muzzle brake will be designed around those tolerances.  Looser the tolerance at the threads, means larger the brake bore...(for safety and liability issues).


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## thestelster (Jul 21, 2022)

Here is one of the first targets from the new barrel and all the work that went into the action.  3 shot group, 280 Ackley Improved, Nosler 140gr. Ballistic Tip factory ammo.  Original wood stock, no bedding.  Looks less than 1/2" group.  Barrel is still not broken in yet, and I'm sure with a good pillar bedding job and good reloads, it will get much tighter.


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## Susquatch (Jul 21, 2022)

Chicken lights said:


> Back to muzzle devices- can you trust factory threads on a barrel to have concentric ID to OD parameters? or as @Susquatch pointed out would the factory care about such tolerances?



The factory will do ok within their tolerances. For liability and cost reasons, those tolerances will be quite wide. If they always did a perfect job, there would be no need for custom work. Similarly, not everyone wants, needs, or can afford custom work - assuming they can even shoot well enough to see the difference. So there is a demand for factory hardware. 

It's all a bit of a crap shoot though. Sometimes factories build a tack driver. More often they don't. The better factories have better averages.


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## Chicken lights (Jul 21, 2022)

thestelster said:


> Trust is a dangerous game!  I'm sure the concentricity is within some tolerance...but what that is, who can say until you actually measure.  And the manufacturer's muzzle brake will be designed around those tolerances.  Looser the tolerance at the threads, means larger the brake bore...(for safety and liability issues).


True, and mixing one barrel manufacturer with another brake manufacturer is going to make it even more of a guessing game, for tolerances. 

Can someone with your skills “fix” barrel threads to be more concentric? I’m guessing no, unless starting with a brake that was undersized.


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## Chicken lights (Jul 21, 2022)

Susquatch said:


> The factory will do ok within their tolerances. For liability and cost reasons, those tolerances will be quite wide. If they always did a perfect job, there would be no need for custom work. Similarly, not everyone wants, needs, or can afford custom work - assuming they can even shoot well enough to see the difference. So there is a demand for factory hardware.
> 
> It's all a bit of a crap shoot though. Sometimes factories build a tack driver. More often they don't. The better factories have better averages.


True. I fall into the no need for custom work category, however it’s an interesting rabbit hole to chase. It’s probably a leftover from playing mechanic, you need to know what the thing is supposed to do, in order to diagnose it before fixing it


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## Chicken lights (Jul 25, 2022)

That’s a fantastic book. It started with bows and arrows, then some history on firearm development, moved onto barrels, then actions and triggers.... I think I’m 105+ pages deep and it hasn’t mentioned any actual shooting tips. Educational and factual, yet fairly easy to read


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