what size should the Internal threads on a muzzle brake, for a .308 cal. and also for a ,338??

I have seen brakes with 1/2 _28, and some with 9/16 - 24 tpi.

what would be best on a hunting gun?

quote:

Originally posted by DLH4570:
what size should the Internal threads on a muzzle brake, for a .308 cal. and also for a ,338??

I have seen brakes with 1/2 _28, and some with 9/16 - 24 tpi.

what would be best on a hunting gun?

It depends on the diameter of the barrel at the muzzle. You don't want to crowd the bore with the minor threads, and, you will want a good torque shoulder for the brake to seat against. I personally wouldn't use anything 1/2 on a .30 cal barrel. Just not enough meat between the minor thread and the bore for my liking. I machine my muzzle brakes directly into the barrel itself to avoid threading issues. It matches the contour perfectly and it looks like it's part of the barrel.

Most of the muzzle brakes and suppressors that I install for the .30 cal rifles are threaded 5/8-24.

On my 30 cal brakes I like to use 9/16x28TPI.

Years ago I designed and built muzzle brakes to go on the Swede 6.5s that came to the US with threaded barrels. That was a 14mm thread. roger

i was going to say something dumb like what kind of brake - shoe or disc, but then i decided not to

14x1.25 is a standard thread used on suppressors and muzzle brakes - same as spark plug thread.

303 guy

is that in MM?? if so that would convert to- 14 tpi X .050

OK anothjer question? how much shoulder should I have on the barrel? the area where the brake will seat is .660 dia. how much shoulder is enough?

quote:

Originally posted by DLH4570:
OK anothjer question? how much shoulder should I have on the barrel? the area where the brake will seat is .660 dia. how much shoulder is enough?

the .660" dia. for the muzzle brake should work well with a 14mm thread if you have reasonably tight thread engagement. The only brake I've seen blown off was on my buddy's rifle that had loose thread engagement.
The bigger the gas engagement area on the muzzle brake the greater it's performance. roger

quote:

Originally posted by bartsche:
Years ago I designed and built muzzle brakes to go on the Swede 6.5s that came to the US with threaded barrels. That was a 14mm thread. roger

Roger,
Were you offering them for sale in an add in Shotgun News?

quote:

Originally posted by craigster:

quote:

Originally posted by bartsche:
Years ago I designed and built muzzle brakes to go on the Swede 6.5s that came to the US with threaded barrels. That was a 14mm thread. roger

Roger,
Were you offering them for sale in an add in Shotgun News?

Yes That was close to 20 years ago! roger

quote:

Originally posted by bartsche:

quote:

Originally posted by craigster:

quote:

Originally posted by bartsche:
Years ago I designed and built muzzle brakes to go on the Swede 6.5s that came to the US with threaded barrels. That was a 14mm thread. roger

Roger,
Were you offering them for sale in an add in Shotgun News?

Yes That was close to 20 years ago! roger

And when you sent them out did you mail them in a little Bull Durham looking fabric bag? If so, I bought two or three of them, still have one left in my parts stash.

quote:

Originally posted by craigster:

quote:

Originally posted by bartsche:

quote:

Originally posted by craigster:

quote:

Originally posted by bartsche:
Years ago I designed and built muzzle brakes to go on the Swede 6.5s that came to the US with threaded barrels. That was a 14mm thread. roger

Roger,
Were you offering them for sale in an add in Shotgun News?

Yes That was close to 20 years ago! roger

And when you sent them out did you mail them in a little Bull Durham looking fabric bag? If so, I bought two or three of them, still have one left in my parts stash.

If you bought three you were my biggest customer. Your use of the term Durham for the bags is interesting as most,I'm sure , on this forum could not connect those bags with that breed of cattle. roger

Cattle? I was thinkin' smokin' tobaccy.

quote:

Originally posted by craigster:
Cattle? I was thinkin' smokin' tobaccy.

I Know****""Bull"" Durham roger

quote:

Originally posted by DLH4570:
303 guy

is that in MM?? if so that would convert to- 14 tpi X .050

Umm, NO
14mm major diameter, with 1.25mm between thread peaks Which translates to something like .551" diameter by 20.3TPI