Gunsmithing Can a muzzle brake effect accuracy?

skeetlee

Gunny Sergeant
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Minuteman
Jun 13, 2008
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I am thinking i want a muzzle brake for my ar varmint rifle. This rifle shoots really nice and i am a little worried that a muzzle brake might effect its accuracy. Whats the truth about this? I have herd pros and cons as far as accuracy goes. I know they are load and the guy next to me will not like it but i dont care about any of that. I want to watch my hits. Thanks lee
 
Re: Can a muzzle brake effect accuracy?

Oh boy, I wonder how many people are going to yell at me for this one, but here it goes.

You could argue the fact that by removing material around the muzzle where the barrel needs to be the tightest might not be a good thing. Sometimes with fluted barrels you can actually feel with a tight patch or a plug where those flutes are because of the material removed from the outside of the barrel opens up the bore an extremely small ammount. The reason why installing a muzzle brake could/can/might/potentially effect accuracy is because it might allow the bore to open up at the crown and muzzle. I dont think anybody can argue that the tightest bore dia. is best at the muzzle. By removing the external metal around the muzzle could allow the barrel to heat up more, but mainly expand ever so slightly, especially with button rifled barrel.

On the other hand, there are plenty of extremely accurate barrels with muzzle breaks, but I think you would squeeze the most accuracy out of a target/varmint rig by leaving a break off.

 
Re: Can a muzzle brake effect accuracy?

I've got a Savage target action with a 260 Shilen barrel. I got about 300 rds thru it and it has always shot around .6. After building a 308 with a brake on it, I decided to add a Vais to the Savage. Still shoots great but know I can see my hits. I've always hated the idea of taking off metal from the muzzle but I haven't noticed any effect. Now maybe on a benchrest rifle??
 
Re: Can a muzzle brake effect accuracy?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: US Handgunner</div><div class="ubbcode-body">Oh boy, I wonder how many people are going to yell at me for this one, but here it goes.

You could argue the fact that by removing material around the muzzle where the barrel needs to be the tightest might not be a good thing. Sometimes with fluted barrels you can actually feel with a tight patch or a plug where those flutes are because of the material removed from the outside of the barrel opens up the bore an extremely small ammount. The reason why installing a muzzle brake could/can/might/potentially effect accuracy is because it might allow the bore to open up at the crown and muzzle. I dont think anybody can argue that the tightest bore dia. is best at the muzzle. By removing the external metal around the muzzle could allow the barrel to heat up more, but mainly expand ever so slightly, especially with button rifled barrel.

On the other hand, there are plenty of extremely accurate barrels with muzzle breaks, but I think you would squeeze the most accuracy out of a target/varmint rig by leaving a break off.

</div></div>

Yell at you? no, but I would have to disagree. I really dont think the muzzle gets as much pressure at the rest of the barrel to cause it to open up. But then again, thats just my opinion, and I have been wrong in the past.

Adding a MB to my Rem700 5R was the best investment I could have made. I can spot my own shots and misses as close as 100 yards, and my shoulder doesnt hurt after 50 or so rounds anymore. as for the accuracy, I think I gained accuracy after the barrel was recrowned. For some reason, I don't think the factory crown was true.
 
Re: Can a muzzle brake effect accuracy?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: USMCj</div><div class="ubbcode-body">
Yell at you? no, but I would have to disagree. </div></div>

You know how some come off extremely aggressive when they disagree instead of sharing ideas. I would have to agree with you in the respect that there are more pros that overcome the cons. Only con I can really think is possibly affecting accuracy in the long run. But like we both know, that's up for debate. So I'm sure we can sum it up by saying that you probably wont notice any decrease in accuracy unless your a bench guy. Certainly the re crowing of a factory barrel should help with accuracy though.
 
Re: Can a muzzle brake effect accuracy?

It may change the point of impact. But the group size shouldn't get worse. On my rifles it has stayed the same whether the brake is on it or not. Just POI changed 3/4" at 100 yards.
 
Re: Can a muzzle brake effect accuracy?

I have found if installed correctly they won't hurt accuracy,
If you handload it may mean you will have to work up a new load because the muzzle break will effect the barrel harmonics. I like them because I like to see the hit.
 
Re: Can a muzzle brake effect accuracy?

Wilson barrels are button rifled.

There is quite a difference in brake design. Buy the best and you will never be sorry.
 
Re: Can a muzzle brake effect accuracy?

I read a good article a while back but I am unable to find it. It's theory was muzzle brakes do increase accuracy but by bleeding the muzzle blast away from the exiting bullet. Like a Holland brake, the quicker the bleed off the better. Allot less turmoil. It got into the expansion chambers and diff effects but the baffle brakes like Holland or Badger are suppose to have the greatest positive effect. Made some good points, wish I could find it.

JamieD
 
Re: Can a muzzle brake effect accuracy?

one of the things I would be concerned about would be hitting a stressed part of the barrel if it is buttoned. If it is cut i wouldn't hesitate to put one on. My 300wsm is getting one and I never really thought twice. plus... it always leaves room for a can in the future!
 
Re: Can a muzzle brake effect accuracy?

Accuracy should remain the same but POI may change.

I will find out soon enough, and If my handloads turn to crap well then I guess the harmonics have significantly changed
 
Re: Can a muzzle brake effect accuracy?

Mark's points on the bore opening up on a hammer forged or button (factory barrel) are correct. The other problems of muzzle brakes are proper installation, being true to the bore, (MOST good gunsmiths can accomplish this without any problems). But the biggest problem I have found is shooters who constantly take the brake on and off. If the brake is not tightened properly it will cause problems. Always one of the first questions I ask when someone has a "bad barrel". Too tight, will constrict the bore. Too loose, will effect harmonics.
 
Re: Can a muzzle brake effect accuracy?

I'm not being sarcastic, so don't take this the wrong way, but what is a properly tightened brake?

At what tightness (ft.lbs) does a bore constrict?

Isn't this akin to say the same about a chamber...say 35ft lbs vs. 100 ft lbs.

Again, just asking not throwing stones.
 
Re: Can a muzzle brake effect accuracy?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: eddief</div><div class="ubbcode-body">I'm not being sarcastic, so don't take this the wrong way, but what is a properly tightened brake?

At what tightness (ft.lbs) does a bore constrict?

Isn't this akin to say the same about a chamber...say 35ft lbs vs. 100 ft lbs.

Again, just asking not throwing stones. </div></div>

That all depends on how thin you made the barrel in relationship to the bore, the make-up of the barrel construction (how hard or soft it is and so on), and the thread pattern. Same as with torque values with different bolts, and different grade of bolts.

Can you distort or make the bore tighter brake? Most definitely. All you have to do is think about what occurs when you apply torque to different size bolts, and what the purpose of torque is in the first place.


 
Re: Can a muzzle brake effect accuracy?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: skeetlee</div><div class="ubbcode-body">I am thinking i want a muzzle brake for my ar varmint rifle. This rifle shoots really nice and i am a little worried that a muzzle brake might effect its accuracy. Whats the truth about this? I have herd pros and cons as far as accuracy goes. I know they are load and the guy next to me will not like it but i dont care about any of that. I want to watch my hits. Thanks lee </div></div>

The EFFECT a muzzle brake has could AFFECT accuracy.
 
Re: Can a muzzle brake effect accuracy?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: skeetlee</div><div class="ubbcode-body">I am thinking i want a muzzle brake for my ar varmint rifle. This rifle shoots really nice and i am a little worried that a muzzle brake might effect its accuracy. Whats the truth about this? I have herd pros and cons as far as accuracy goes. I know they are load and the guy next to me will not like it but i dont care about any of that. I want to watch my hits. Thanks lee </div></div>

My experience:

First, I don't buy into the wives tale that it degrades accuracy. However there are a few things that go into installing a brake that (in my opinion) need to be observed.

First, I think a brake with radial ports is important from an accuracy standpoint. The moment the bullet leaves the crown the gas plume begins to out accelerate the bullet. It has to because it has far, far less mass than the bullet. If it weren't the case then guns wouldn't be so loud. It will continue to do this until the speed is lower than the bullet. The kinetic force behind that gas plume is real and significant. If it were to favor one side more than the other the odds of it altering the projectile's path increases. Sometimes dramatically.

That being said we'll conduct a simple demonstration; just stick your hand outside of a car window as you drive down the freeway and feel the effects gas pressure can have. Now multiply by several orders to replicate the effects the gas charge has behind a bullet. Shouldn't be too difficult to appreciate the benefits of a symmetrical/uniform dispersion of gas. The practical application from this comes from years ago when I worked on a sniper rifle development project for a foriegn government. My boss and I had differing opinions regarding brake design. He was intent on using a brake that would mitigate dust signature and muzzle climb. I advised against it. In the end I won. His brake created elevation problems with the groups. Mine didn't. The Marine Corps Summer Team found this out as well back when M-16's were first coming into play in service rifle at Perry. The AMU whooped us good in the early 90's when they made the jump from 14's to 16's. Quantico/PWS followed suit by bringing out a line of national match m-16's the following year. Only one problem, they still had muzzle compensators and this created elevation issues at the 600. It would be why one will rarely find a compensator on a NM AR today used for competitive shooting.

Next, I make my own brakes for the most part, but when I order one (which I haven't done for some time) I make sure I make it/have it made with the largest ID thread possible. This ensures that I leave as much wall thickness between the major ID of the barrel and root diameter of the threads. The pressures at a muzzle are real and they are still quite high. Over time I worry that a barrel may begin to yield or "bellmouth" at the crown. leaving as much wall thickness as I can on the barrel in my mind helps to mitigate this.

Last, thread fits. Classes of threads are great as they give a qualified dimension to run to. I personally feel that any threads on a barrel, be it the tennon or the muzzle, need to be fitted individually to whatever part they are being assembled to. This would include muzzle cans as well. So, I make them as tight as I can get away with while avoiding issues like galling or seizure. Surface finishes have a great part in this.

Just my two bits.

Chad

 
Re: Can a muzzle brake effect accuracy?

I had a brake installed on a Model 12 Savage heavy barrel in 308. It helped quite a bit with recoil, but it did change my impact about 2" higher at 200 yards. Unfortunately, the 2" difference does not stay constant out to 1000 yards so the ballistic tables and calculations only get me close.
 
Re: Can a muzzle brake effect accuracy?

Perhaps, if you only reason for getting a brake is to watch hits, you may do well to spend a lot less money on the on line training here, or a day at Rifles Only, and learn the technique for driving the rifle such that you are able to see the round, regardless of brake/no brake.

Not being sarcastic, a decent brake plus gunsmithing will run about 250-300 bucks. Plus, you WILL learn a lot of other im-pout-tant stuff, while banging the heck outa somone else's steel!

Perhaps Lowlight can chime in here?
 
Re: Can a muzzle brake effect accuracy?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: gundoktr</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: skeetlee</div><div class="ubbcode-body">I am thinking i want a muzzle brake for my ar varmint rifle. This rifle shoots really nice and i am a little worried that a muzzle brake might effect its accuracy. Whats the truth about this? I have herd pros and cons as far as accuracy goes. I know they are load and the guy next to me will not like it but i dont care about any of that. I want to watch my hits. Thanks lee </div></div>

The EFFECT a muzzle brake has could AFFECT accuracy. </div></div>

THANK YOU gundoktor. I thought I was the only asshole who would point out the misuse of EFFECT, when the OP probably meant to use AFFECT.

It ain't easy being a grammar Nazi.
 
Re: Can a muzzle brake effect accuracy?

I don't think the braking effect should affect accuracy of itself.

But if installing the brake involves mounting additional mass onto the muzzle, that mass can alter the barrel's harmonic frequency to the point where the accuracy load can need to be redeveloped.

Think about what happens when you add a weight to the arm of a tuning fork.

I don't favor brakes, and suggest there are other ways to manage muzzle jump that don't involve them.

Greg
 
Re: Can a muzzle brake effect accuracy?

Another 'hider had a brake made by a local smith. Granted, the 'hider wanted it made differently than his normal design.

After it was installed, the rifle acted like it had a broken scope or something. This was on an LTR BTW.

We went to the range together to experiment and figure out what was up. I put it on paper at at 100 yards. It produced a 2 MOA wide/8 MOA tall "group" (if you could call it one).

I screwed the brake off and fired again. The POI changed 20 MOA without the brake. Once centered, I produced 2 3/4 MOA groups in a row with the rifle using factory ammo.

Yea, a brake can affect accuracy.
 
Re: Can a muzzle brake effect accuracy?

Yes, a muzzle brake can worsen accuracy. But if it is a good brake installed by a competent gunsmith, should not be noticeable.

I would only put on a muzzle brake if the recoil of the rifle is too much for you, or if spotting your own shots and not coming off target after shooting is important to you.

For a varmint gun, I would probably stay ago from muzzle brake.
 
Re: Can a muzzle brake effect accuracy?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: _9H</div><div class="ubbcode-body">Another 'hider had a brake made by a local smith. Granted, the 'hider wanted it made differently than his normal design.

After it was installed, the rifle acted like it had a broken scope or something. This was on an LTR BTW.

We went to the range together to experiment and figure out what was up. I put it on paper at at 100 yards. It produced a 2 MOA wide/8 MOA tall "group" (if you could call it one).

I screwed the brake off and fired again. The POI changed 20 MOA without the brake. Once centered, I produced 2 3/4 MOA groups in a row with the rifle using factory ammo.

Yea, a brake can affect accuracy. </div></div>

If there was a 20-MOA change with and without the brake then the barrel thread job was crap and or the brake was.
 
Re: Can a muzzle brake effect accuracy?

http://www.centershotrifles.com/gallery/img/300WINMAG_100_1291_TRGT2.jpg
400 yard group 300 win mag w/csr brake


http://www.centershotrifles.com/gallery/img/BluRem700Brux10TMannersMuscle_trgt.jpg
200 yard group with muscle brake.

I think a properly installed and designed brake will not hurt your potential accuracy.

Over time issues with some brakes will CAUSE poor accuracy.
example; Brakes made out of sub-standard or soft material. especially side baffled style brakes.

We have all seen pics of the baffle surface pitted and eroded from the blast of gas and carbon comming down the tube. I have seen the leading edge of these baffles press steel and roll a bur into the thru hole thus constricting the bullets clearance. These rifles and Specialty Pistols had sudden loss of accuracy and thats why they were brought in to me. I learned this lesson during the development of my brakes. This neccesitated heat treatment of the first run and switching to a harder material for future production.

Skeetlee, I do not think you will be disapointed by a brake affecting your accuracy negativly. Just pic a good brake there are many out there.
 
What about overtightening a brake? I've had that affect accuracy, and there are gunsmiths out there who swear by Loctite and a hand-tightened 'muzzle device' whether it's a compensator or a brake.
 
Skeet,
For live varmint shooting a brake is hard not to like, other than the plugs and muffs. We run Harrells brakes on all of our rifles except the walk around sporters. Makes seeing the hits a cinch. For 30 dollars they are a precision built unit. I always bore after the brake is installed, the runout before boring runs from nothing to .0005 on the ten or so brakes I have installed. Bore after threading then reset up on your barrel OD to profile the brake. They have several sizes to go with various barrel diameters, usually have them within three days after ordering. Super people to deal with. Dale
 
I have found that in most cases with a properly installed brake you will be ok. Although on a few occasions I have found that the muzzle suffered from a bell mouth condition which was discovered after slugging the barrel. I slug the barrel before fitting and then again after fitting to insure no change in the bore. I actually just finished one that suffered from this condition