Adding a brake

[J E Custom]

I will comment on some of the issues discussed on some of the later post that I have observed
during the test that I have preformed.

First. I don't want to discredit any brake, just explain cause and effect.

The issue about muzzle brakes effecting accuracy - If the bore of the brake is centered on rifles bore there should be no effect on accuracy, if it is properly installed and has a balanced discharge
of gasses.

The bore diameter does have an effect on the effectiveness of the brake if it is not correct. the minimum diameter can be less than .020 as long as it clears the bullet path, "BUT" the shock wave in front of the bullet can effect accuracy/bullet flight, if it is to close to the bore diameter of the brake, even though the bullet is clear, before the brake starts to work (The gas is expelled out the ports/holes just after the bullet exits. If you look at some of the high speed pictures, you can see the shock wave in front of the bullet while it is still in the brake. this is/can cause the bullet to yaw
if everything is not perfectly aligned and cleared enough.

On one test brake I drilled the proper sized bore hole and tested it against one that was Bored true
after timing it. The drilled brake did not shoot as good as the bored brake and after the test I found the drilled brake was less than .002 thousandths off center (+.001 on one side and -.001 on the other side. So reaming or drilling this bore hole is not acceptable and boring this hole is the only
true way to avoid another potential problem. When cutting the barrel tenon the threads should also be cut off the centerline on the barrel especially if the bore is not perfectly true to the out side of the barrel. this way the barrel threads will be centered to the bore and the brake bore will also be centered with the bore. Everything to do with the action, bolt, chamber. barrel tenon and muzzle
"MUST" be centered and true to the bore if you expect a high level of accuracy.

If the bore diameter is bigger than necessary for the proper clearance, it loses efficiency because it allows more gas to exit the front of the brake causing backwards thrust, increasing recoil.
(Size Matters) Sorry I couldn't pass that up. Ha Ha.

Top ports should not damage a rifle as long as it is being held/supported by your hand like in an offhand position. But, if it is restrained from moving down, there can/may be damage to the bedding and/or the stock. especially if it is resting on something solid, as in the videos.

I replaced all of my top port brakes because I did not want to beat up the bedding or the stock.
The brakes I replaced were all accurate and good shooters but I noticed that instead of seeing the hit , after firing, I found my self looking at the ground below the animal when shooting off hand.

Is the downward flexing hurting the barrel ? I cant be sure, but it cant help, and any force great enough to bend/flex a barrel cant be good for it and over a long period of time could work harden the barrel or at least change the heat treat/stress relieve in it. not to mention the effects on stocks and bedding.

I have salvaged most of the top port brakes and used most of them by taping the holes 95% and screwing a bolt in until it is flush with the inside of the port (Not the bore hole). By tapping the hole shallow the bolt binds up and welding is not necessary and all that is left is to cut the bolts off and turn/grind them flush.

You can plug them and start drilling a small hole in the first top port and enlarging it until it produces a neutral effect and just keeps the muzzle from any movement. the problem with doing this is that you have to use only one load, if you change loads you have to retune/drill the top port
to match that load.

So I elected to plug the top ports and use them plugged .

These things are not opinions, They are things that were observed by myself and others helping with the test and slow motion Videos for all to see.

J E CUSTOM

 

[Edd]

On one test brake I drilled the proper sized bore hole and tested it against one that was Bored true after timing it. The drilled brake did not shoot as good as the bored brake and after the test I found the drilled brake was less than .002 thousandths off center (+.001 on one side and -.001 on the other side. So reaming or drilling this bore hole is not acceptable and boring this hole is the only true way to avoid another potential problem.

J E CUSTOM

Are you saying they should be bored true while installed on the barrel?

 

[J E Custom]

Are you saying they should be bored true while installed on the barrel?

Yes. If the barrel is set up true to the bore, and the threads are cut, the threads are also true to the bore. then after installing the brake and timing it (While the barrel is still set up true) the boring process will make the muzzle brake bore also true to the barrel bore because the threads may shift
and find there own center. boring after the brake is made up tight will assure that if there were any movement no matter how slight, the muzzle brake bore will be absolutely true to the rifle bore.

With good thread fits this is not really an issue as long as the rifle barrel was set up correctly and true to the bore center line before cutting the threads, and the muzzle brake is machined true to the
threads also. Boring the muzzle last is just more insurance that you have it as near perfect as possible.

No matter how accurate the muzzle brake is, it wont be centered if the rifle barrel is not set up right and cut true to the bore.

This is the reason that most smiths recommend a lathe for cutting the tenon and threads for brake installation.

If all work is performed correctly ordering a brake and installing by a competent gun smith will not be a problem. When I can, I still like to do all the work so I know the final Quality of the install.
With the cost of shipping and insurance this is not always practical though.

J E CUSTOM

 

[StaMic006]

My STW sports a 26" shilen tube and while recoil isnt too bad for a 9lb gun scoped contemplating adding a brake so can actually see critters fall and not rely on my buddy. Curious if any of you guys have done it. Im hesitant as talked to a couple folks and would make my overall length around 28" I could always cut to 24 recrown but that freaks me out a bit as its already really accurate and afraid to jeapordize it.

If it's legal where you live bypass the brake and go straight for a suppressor. I had a brake installed on my rifle when it was built while I was waiting on my tax stamp and I wish I'd saved the money. A "can" will give you the recoil reduction to stay on target and save your ears too.

 

[Brewer]

Yes. If the barrel is set up true to the bore, and the threads are cut, the threads are also true to the bore. then after installing the brake and timing it (While the barrel is still set up true) the boring process will make the muzzle brake bore also true to the barrel bore because the threads may shift
and find there own center. boring after the brake is made up tight will assure that if there were any movement no matter how slight, the muzzle brake bore will be absolutely true to the rifle bore.

With good thread fits this is not really an issue as long as the rifle barrel was set up correctly and true to the bore center line before cutting the threads, and the muzzle brake is machined true to the
threads also. Boring the muzzle last is just more insurance that you have it as near perfect as possible.

No matter how accurate the muzzle brake is, it wont be centered if the rifle barrel is not set up right and cut true to the bore.

This is the reason that most smiths recommend a lathe for cutting the tenon and threads for brake installation.

If all work is performed correctly ordering a brake and installing by a competent gun smith will not be a problem. When I can, I still like to do all the work so I know the final Quality of the install.
With the cost of shipping and insurance this is not always practical though.

J E CUSTOM

so in my opinion, I would say that as long as you are cutting threads on a lathe, and your bore is in a live center, there is absolutely NO reason to cut the break on the rifle. if you get your threads on center axis, you are good. AND if you bore the muzzle and cut or tap threads while the break is chucked, you had better be within .0001 of concentricity or you need a new lathe.

anybody that would use a die to cut threads on a rifle is either stupid or unfit for their position (the emperor has no clothes!)

 

[J E Custom]

so in my opinion, I would say that as long as you are cutting threads on a lathe, and your bore is in a live center, there is absolutely NO reason to cut the break on the rifle. if you get your threads on center axis, you are good. AND if you bore the muzzle and cut or tap threads while the break is chucked, you had better be within .0001 of concentricity or you need a new lathe.

anybody that would use a die to cut threads on a rifle is either stupid or unfit for their position (the emperor has no clothes!)

Your opinion is correct as far as I am concerned with the exception of using a Tap To threads in the brake. So if the brake is set up in the lathe and the threads are cut, (Not Taped) and bored at the same time to the proper clearance it should be fine. Set up sometimes takes longer than the job it's
self in order to get the barrel as near perfect as possible.

So with the brake threaded, fitted and timed, why not bore it then if possible. I have installed brakes that were ordered and found them not as concentric as I would like and had to bore the bore hole several thousandths in order to get it concentric with the bore. I also take a cleanup cut on the outside of the brake to assure it is concentric also.

The only reason that I like to bore the brake last is, It guarantee's that the bore hole is as concentric as possible. This is not always possible, if you order a brake and have it installed by another person/smith. If the brake is already threaded and bored in two different set ups it can
be off a little (Not enough to have a bullet strike) But not perfect.

Being anal about trueness is just a characteristic of many gunsmiths on this site and in some cases may not be necessary, BUT it is a good trait if they do it in all things. It is called craftsmanship.

Eliminating any possible issue, will reduce the number of possible problems.

J E CUSTOM

 

[Timber338]

Being anal about trueness is just a characteristic of many gunsmiths on this site and in some cases may not be necessary, BUT it is a good trait if they do it in all things. It is called craftsmanship.

Eliminating any possible issue, will reduce the number of possible problems.

J E CUSTOM

Well said. I could not agree with this more.

 

[Brewer]

I think in theory, tapping is at least as good as cutting. especially if you consider how match grade rifle barrels are chambered, or if you break the insert or get locked in too early or late. with a tap, not much room for human error. tapping is more expensive because you have to have all the taps but if you use your tail stock to hold your tap, it can go nowhere but dead (+/-.0001) center. better yet, if you use your floating reamer holder, you are even better off.

again, I don't think it matters what method you use because it has more to do with the guy running the machine than what we are talking about. and I am sure they way you do this is more than adequate for your customers. I would have no reservations to taking a rifle to you to have it ported

 

[J E Custom]

I think in theory, tapping is at least as good as cutting. especially if you consider how match grade rifle barrels are chambered, or if you break the insert or get locked in too early or late. with a tap, not much room for human error. tapping is more expensive because you have to have all the taps but if you use your tail stock to hold your tap, it can go nowhere but dead (+/-.0001) center. better yet, if you use your floating reamer holder, you are even better off.

again, I don't think it matters what method you use because it has more to do with the guy running the machine than what we are talking about. and I am sure they way you do this is more than adequate for your customers.

I would have no reservations to taking a rifle to you to have it ported

Thanks'

Again , not to start an argument but Taps tend to find there comfort zone and may /can Move off center because of the sharpening. (All teeth are not as sharp as others on the same taps just like chamber reamers rarely cut the same from one flute to the next.

Even if they are chucked up in the tail stock they can/will move off center sometimes.
Drills can/do move of center also even though they are chucked up there is enough flex in
the bit to allow it to move off center.

One of the main problems I find with taps is the tendency to taper the threads based on wear(The more a tap is used the more it wears on the front because the front is where most of the cutting is done) so the taped hole ends up tapered just enough to make a quality fitting thread get tighter as it is made up.

I have bought muzzle brakes that were tapped and had to custom fit the brake to the barrel tenon
to get the proper fit. I have not found this to be the case when a thread mill was used on the muzzle brake.

Again, I am not comfortable with taps and dies for any gun work (Just me Maybe) except maybe scope/site mounting holes.

Thanks

J E CUSTOM





Cutting threads with the single point tool in a lathe is still the best and most accurate method In
My opinion

 

[Brewer]

JE,

I thought after I made my last post that I should have said something about not fighting. this is a friendly conversation as far as I am concerned.

you are correct about the sharpness of a tap and/or drill bit. especially on longer holes, when the hole starts to move at all, it becomes exponential very quickly. however, once you have the hole drilled, reamed or bored, I would find it very hard to believe that if you introduced a tap (dull though it be) into that straight hole , it would want to go anywhere but the path of least resistance, which would be right smack dab in the middle of the hole.

now, having said that. anything that is bigger than 1/2" I cut threads with a boring bar with a threading insert. and I have never had a problem with any of the suppressors that I have made on a .223. even ones that were 9" long. I over size my holes .020" and I rarely notice a point of impact shift of more than 1/2" at 100 yards. and I believe you could contribute most of that to barrel harmonics, not concentricity.

but that is just my experience. I perform all my functions (if possible) when the piece is chucked. I rarely have to dial it in because I turn my outside when its on the rifle and all the inside work is don't during one chucking.

I also either build or buy blanks for breaks, I ream a bigger hole and cut the threads myself so I don't have to deal with a piece that is out of center.

of course, most factory barrels are out of center somewhere in the neighborhood of 5 to 15 thousandths. so making them look good on the outside is a little tricky I either have to get the outside of the barrel fudged to center or fudge your break to the barrel.

Id be interested in hearing how you do this with factory barrels because it seems like there has to be a better way.

 

[J E Custom]

On factory barrels they are rarely concentric with the bore so I indicate of the bore and then turn
the OD to the major diameter of the thread side and pitch and then thread. a few thousandths out
of concentric with the bore does not hurt the threads because they are centered on the bore.

If the barrel is more than a couple of thousandths , it does make it harder to blend the brake to the barrel.

I also turn the barrel shank true to the bore (Just enough to clean it up) before I start a chamber just to make it more consistent while firing. (I still indicate the chamber end off the bore before any threading or chambering is done) (It makes me feel like I have done everything possible to assure
an accurate rifle).

I have gotten many good ideas from guys on this site that will share there experiences and I always hope I help someone also.

J E CUSTOM

 

[Brewer]

JE, since I have officially hijacked the thread here...

so you indicate the bore with a bore rod and bushing I assume, but how do you chuck the tapered in of the barrel to do that?

 

[J E Custom]

JE, since I have officially hijacked the thread here...

so you indicate the bore with a bore rod and bushing I assume, but how do you chuck the tapered in of the barrel to do that?

I have an adjustable jaw chuck (Each jaw can be moved independent of each other to center a off center barrel OD.

You can use the live center in the bore, but it can damage the crown so I prefer chucking on the outside and using brass buffers under each jaw to make up for the small amount of taper.

J E CUSTOM

 

[Brewer]

it was the taper I was thinking about, I am familiar with an independent chuck (3 and 4 jaw). brass buffers are a good idea. does that take care of tooling marks too or do you tape the barrel in addition?

on the live center, you can make or buy brass inserts that cap the live center and keep the crown from getting damaged.