Flash hider/brake

[Bill Alexander]

5/8-24 leaves very little shoulder for the crush washer to act on if the barrel is a typical .gov profile with a 0.700 diameter behind the thread. The 5/8-24 thread was designed for the AR10 and runs off a 0.875" gas block which will have a 0.800"/0.840" or bigger shoulder behind the threads. The lack of support for the crush washer is not conducive to a well aligned muzzle device.

The 9/16-24 is the original 30 cal size before Armalite changed to stop people using FAL stuff on the AR10. We adopted the size as it allows AR15 sized muzzle attachments to be used ( do not like a flash hider the size of a trash can on a small frame gun) but precludes someone just screwing a 5.56 unit on without looking at the size of the hole down the middle. (read liability lawyers). As the usage has increased so has the diversity of attachments. There are a few things that cannot be found in 9/16-24 but be aware that the 1/2-28 thread size is easily opened up. YHM makes excellent crush washers for this tread size but I note that they do not have the flash hider brake but do have thread protectors.

I think that this mid size thread size is very well suited to the Grendel and that like the guns themselves, the ammo and the magazines we will see more offerings as the caliber grows in the market. It is one of the prices of being early to the party, but if you want to follow the flock then you probably would not be reading this. anyway.

[BjornF16]

I believe the Satern barrels he is looking at are .850" or .890" at the muzzle (at least that is what is mentioned in another thread as immediately available from Satern).

[outlaw45]

Not looking for a bull barrel. Hbar style is fine.

[outlaw45]

Just spoke with the folks a Satern. They said the 5/8-24 is the most popular.

So let me get this straight. As long as I get the threading correct, I can use a comp/flash hider/brake from a larger caliber, like a 7.62, on a smaller caliber gun like a 6.5? You don't need to match up the brake/comp caliber to the caliber of the gun you're putting it on.

[LRRPF52]

Just spoke with the folks a Satern. They said the 5/8-24 is the most popular.

So let me get this straight. As long as I get the threading correct, I can use a comp/flash hider/brake from a larger caliber, like a 7.62, on a smaller caliber gun like a 6.5? You don't need to match up the brake/comp caliber to the caliber of the gun you're putting it on.

Yes.

[noone]

Knowing the difference between a flash hider and muzzle brake may simplify your shopping. There are a few keys to purchasing either one:
1. Matching the internal diameter of the muzzle unit to the caliber of your rifle so the projectile has sufficient room to clear the brake without hitting it.
2. Knowing the thread pitch and direction on your rifle (right or left handed threads).
3. Finding out if there are any legal restrictions on a flash hider where you live. (Some jurisdictions allow brakes, but not flash hiders.)

Then you can start to evaluate the price and performance of the muzzle devices you are considering. There have been quite a few articles written comparing how much recoil reduction, flash reduction, noise increase the various units produce.

[outlaw45]

Ok I ordered a Satern barrel. I want a flash hider with 5/8-24 threads. What do you recommend?

Possibly a AAC Blackout? From there website they only made 5.56 and 7.62.

[Daveworkslocal]

JP Enterprises Recoil Eliminator. Shot 200rds today and not even the slightest of discomfort. The BEST muzzle break I've used yet. Turns the Grendel into a 20lb 5.56 gun.

[outlaw45]

Sorry not looking for a brake. Just a flash hider.

[ericv]

Ok I'm thinking of the AAC Blackout flash hider. 9/16-24 threads. Iowa doesn't allow suppressors but maybe someday.

I am in New York and we can't even have the threads, go figure. Muzzle brake must be welded.

[ricsmall]

I am in New York and we can't even have the threads, go figure. Muzzle brake must be welded.

yea, im surprised anyone can have threads on a barrel as dangerous as they are!

[rasp65]

The threads can be very sharp and you might hurt someone or yourself on them.

[noone]

I am in New York and we can't even have the threads, go figure. Muzzle brake must be welded.

A very small tack weld still counts as a weld. If in the future you want to get rid of it, a little work with a file, or small grinding tool like a Dremel, or Fordam tool would quickly remove a small tack weld. IIRC, the weld is so that the muzzle device is afixed so that you can't simply use a tool such as a wrench to remove it. Some states count silver solder the same as a weld because that makes the brake "permanently" fixed to the barrel so a simple tool can't remove it.

Just to be safe though, check the laws, and definitions used in the laws in your area. In many states, they just say that the device has to be "permanently" fixed onto the barrel, and "permanently" is often described in different ways.

[outlaw45]

Ok not looking for a muzzle brake, just a flash hider. Is there any other concern I need to worry about other than getting 5/8-24 thread to match my barrel and making sure my bore diameter is at least 6.5mm? Most likely will have to get a 7.62 flash hider.