Do-It-Myself Muzzle Brake

[Junior1942]

The recoil of my 10" bull T-C Contender 30-30 is tolerable, but I don't like the muzzle jump. I'm thinking of taking a 1/8" HSS bit and drilling a hole in the top of the barrel near the muzzle. Thoughts?? Tim, whatcha think???

[nhrifle]

Without a good way to debur the bore, that may cause loss of accuracy and cut jackets or deformed boolits. I would either make a piece that clamps onto the muzzle or thread it and install a threaded brake.

[NSP64]

Junior, I would put a lead slug in the barrel where you plan on dilling to back it up so it doesn't burr.

[B R Shooter]

The lead slug trick works. I would drill several once set up.

[Junior1942]

Junior, I would put a lead slug in the barrel where you plan on dilling to back it up so it doesn't burr.

That's a good idea. Also, it seems to me a couple of medium velocity j-word bullets would blow out any burrs. My worry is aligning the bit to the bore center.

[Jim]

Junior, mark the hole locations with a pencil or Sharpie Marker and center punch first. If you try this free hand, that bit is gonna walk all over the top of the barrel. Don't ask me how I know.

[Reg]

Better do a bit more research first. That isn't how muzzle breaks are made and that lead slug will not stop a internal burr from forming and unless you have access to something like a EDM, you will not be able to get rid of that burr no matter what. Firing bullets down the bore will not do it.
Most muzzle breaks have a internal diameter about .030 larger than bore dia. Best to have the end of the barrel threaded to fit it but could possible be clamped on.

Also it is very doubtful that one hole will reduce muzzle jump, generally it takes several.

[1Shirt]

Junior, If you decide to do it, let us know the results please.

And Jim, you obviously had some results, what were they?
1Shirt!

[B R Shooter]

Better do a bit more research first. That isn't how muzzle breaks are made and that lead slug will not stop a internal burr from forming and unless you have access to something like a EDM, you will not be able to get rid of that burr no matter what. Firing bullets down the bore will not do it.
Most muzzle breaks have a internal diameter about .030 larger than bore dia. Best to have the end of the barrel threaded to fit it but could possible be clamped on.

Also it is very doubtful that one hole will reduce muzzle jump, generally it takes several.

Ever hear of "Magna Port"? You unload some of that gas before the bullet leaves, it will help. Is it as good as a full blown brake, probably not.

[Junior1942]

Better do a bit more research first.....

That is exactly what I'm doing here.... And trying to do it for far less than $200+.

[Junior1942]

Ever hear of "Magna Port"? You unload some of that gas before the bullet leaves, it will help. Is it as good as a full blown brake, probably not.

I had a 10" SBH 44 mag pistol I sent to MagnaPort. The two trapezoidal holes they cut beside the front sight lessened muzzle jump substantially. Here as then, I'm not concerned with recoil reduction, just muzzle jump reduction.

[Jim]

.....And Jim, you obviously had some results, what were they?
1Shirt!

I'm glad to confess my mistakes in hopes it will stop somebody else from attempting it. I did a redneck porting job on an old 'Bubba Special' 2A1. The stock was butchered and the barrel had been cut and crudely recrowned, so I figured I had very little to loose.

Rather than center punching the holes prior to drilling, I thought I could keep the bit located. Wrong answer, Jim. I monkeyed up the top of the barrel with 'foot prints' from the bit walking around.

After buffing the foot prints, I center punched and drilled four holes with a 5/32" bullet point bit and then chamfered the holes by hand with my Lyman case tool.

I got inside the muzzle with a bright pen light and didn't see any burrs. That doesn't mean there were none there, I just couldn't see any. The rifle still shot to POA at about 50 yards, but the porting didn't change anything that I could tell.

[Nazgul]

I have had 2 barrels done by SSK Industries. The cost was around $200. Cannot say enough about their service. Very good reduction in jump.

Don

[John Taylor]

I have ported more than a few 44 mags by boring three holes on each side of the front sight. I use a milling machine and carbide endmill. Use Cerrosafe in the bore, much easier to get out than lead

[I'll Make Mine]

The other issue that no one has mentioned relative to drilling the bore is that you really, really want the hole to come out into a groove, not on a land.

The simplest way to do this would be to go ahead and drill the hole(s) you want (ideally, if you have the tooling to do it, you might want to angle the holes so the exterior is 5º to 10º back toward the breech from the inner end), then counterbore the barrel past the holes to around .020 over groove size; that will clean up any internal burrs, remove any issues with the hole being on the lands, and give some free space around the bullet to make the ports act more like a real muzzle brake -- but the counterbore will be invisible unless you're examining the muzzle close up.

FWIW, Magna Port uses EDM (that's how they can produce holes that aren't round); they also do some operation on the inside to prevent shaving jacket or lead where the holes inevitably intersect a land (something that can't possibly be done with a drill or end mill through the same size hole). An EDM isn't at all beyond the reach of a home shop machinist to build; I've seen them made for under $50 (and this is for a tool that can be reused, rather than paying someone for a job and having to pay again if you want it done on another revolver).

[B R Shooter]

I don't know how you could get the holes/slots in a groove and make it look good on the outside. While it makes sense, for looks sake, how do you do this?

[I'll Make Mine]

Well, that's the problem, B R. One hole on top, or a pair (one on either side of the sight), it's just a matter of calculating how far back from the muzzle for the twist to bring a groove (of known position at the muzzle) under the hole. If you need more than that, it's much more complicated, which is why few barrels were ever done this way before Magna started doing them with EDM.

If you counterbore, hole position doesn't matter -- drill 'em where you want 'em, then counterbore from the muzzle past the ports. If you do two sets of two or three holes either side of the front sight, you could get away with half to three quarters of an inch of counterbore -- which will mean you don't give up much velocity to effectively shortening the barrel. Counterbore could be done with a plain twist drill, then follow with a ball end mill to produce the crown at the new "internal muzzle."

[John Taylor]

Well, that's the problem, B R. One hole on top, or a pair (one on either side of the sight), it's just a matter of calculating how far back from the muzzle for the twist to bring a groove (of known position at the muzzle) under the hole. If you need more than that, it's much more complicated, which is why few barrels were ever done this way before Magna started doing them with EDM.

If you counterbore, hole position doesn't matter -- drill 'em where you want 'em, then counterbore from the muzzle past the ports. If you do two sets of two or three holes either side of the front sight, you could get away with half to three quarters of an inch of counterbore -- which will mean you don't give up much velocity to effectively shortening the barrel. Counterbore could be done with a plain twist drill, then follow with a ball end mill to produce the crown at the new "internal muzzle."

Having designed, built and tested brakes over many years I can say your counter bore will not help. The whole idea is to direct the gas pressure in a different direction than following the bullet. Holes all the way around the barrel will reduce the recoil from the gas pressure but the barrel will still rise on a pistol. That's why the holes go on ether side of the front sight, to keep the barrel from rising as much. With a counter bore the gas is not redirected, it just follows the bullet and does not reduce recoil. I know this from testing brakes of different designs. Also the holes do not need to be lined up with the grooves. If there are no burrs on the lands they will not shave lead. Any small burrs are usually gone after a few shots, even with cast bullets. By the time the bullet gets to the brake there is not enough pressure to upset the bullet to expand it anymore so it does not have any way of shaving lead. There are a lot of theories out there but until you test them they are just theories.
On most pistols I put three holes on each side of the front sight. Holes need to be small and at a right angle to the bore, about 1/8" works fine. Slanting the holes back will not help the reduction in recoil but will hurt the ears more.
Magna port has an advantage of no burrs from the start but I think they would have a better brake with more holes. That would be more 90 degree angles to redirect the gas. I tried a brake that had six slits inline with the bore and there was no reduction at all because the gas pressure had no turn, it was still going the same direction as the bullet. This brake looked more like a flash hider.

[dragonrider]

Just as an idea look at this. I made this one and installed in my Ruger Mark II, it is far more effective than I expected it to be. The hole in the middle is for the front sight though I do not use it as I have an Aimpoint on it. I threaded it 5/8"-40 TPI.

[MBTcustom]

I totally agree with John Taylor on this one (not surprising considering the gap in experience).
The burrs in the barrel will go by-by after just a few shots.
I would be reluctant to drill them with a standard drill bit though and would probably use a 1/8" carbide endmill in a milling machine turning at high RPMs.
I agree that three holes on either side of the front sight is minimum to see any sort of reduction in barrel rise.
From a touchy, feely, point of view, I would mention that the human eye is capable of seeing uneven patterns in a series of holes very easily, and if they are not within .010 of correct and true position, then it will look like dooky.

However, if you do it right, with a drill press and the correct drill bits, then it is possible to hit those numbers, and it will look quite good.
Push a cleaning rod with a patch on a jag up from the breach and stop about 1 1/4" from the muzzle.
Melt some cerosafe chamber casting alloy and fill er up to about 1/8" of the crown.
Use white out, or a white paint marker, as a layout die on either side of the front sight.
Use a pair of calipers to scratch the paint (Do not go through it! it will scratch your blued finish! Use tape on the opposite jaw to protect the tip of the barrel.)
Scratch the pattern in at even intervals .250, .500, and .750 radially from the end of the barrel.
Use the inside nibs of your calipers to scratch linear lines, using the front sight as a guide. You want your calipers to be set to at least .075 so that your holes don't bite the front sight.
So now you have six "X marks the spot" locations, evenly spaced .
Get a hard center punch and put it in your hand drill to sharpen it to a very sharp point, almost like a scribe.
Mount the barrel securely in a padded vice.
Put on your reading glasses (a magnifying visor is better) and very carfully get the point of the scribe right in the middle of the Xs and tap it with a small brass hammer.
Next, mount the punch back in your drill and resharpen it more like a regular center punch, and go over all the locations again. Just tap them.
Go over them one last time and hit the punch with a little force this time.
Now, I am assuming that you have a drill press and a drilling vice?
Mount the barrel in the vice, and eyeball the holes as being strait up. Take a square and set the main beam on the surface that the vice is sitting on. Position the blade so that it touches the crown of the barrel. Use your eye to move the blade so that it devides the bore exactly in two when you are looking at the crown of the barrel. Move your head up and see if the row of three holes is actually strait up. Re-position the barrel and test it again. Keep at it until those holes are actually strait up as close as you can tell.
Now, mount a #1 center drill in the chuck of your drill press and bump the switch. If it seems like it is wobbling, then loosten the chuck and try it again. Keep dinking with it until that center drill runs true.
Now, get your visor back on your head and very carefully center drill each of those cross points. Try to let the center drill "float" into the punch marks that you made.
Now get a new #39 sized drill bit (that's .0995) and drill all three holes using plenty of dark cutting oil.
Next, get a new #31 sized drill bit (.120) and drill-ream those holes using plenty of dark cutting oil.
Next, take a 1/8" reamer (you can get all these tools for cheap on e-bay) and ream those holes using dark cutting oil.
Voila! There's one side done.
Repeat this process on the other side.
Use a brass rod, and a soft faced mallet to drive the cerosafe slug out the end of the barrel.
Clean the oil out of the holes and off the barrel, and use cold blue in the holes to make 'er look like you knew what you were doing.
Go shooting, live well, and prosper.