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Muzzle break install - crush washer or Jam nut

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Looking for the expertise of the forum. When installing a muzzle break is it better to use a crush washer or Jam nut? Is there a specific reason to choose one or the other?
 
Use whatever is supplied with the muzzle device. Or what's recommended by the manufacturer. The vast majority call for crush washers (with or without shims as needed). All the ones I've installed so far have used crush washers. I even ordered up some spares to have in case I needed to remove the muzzle device and then reinstall it later (you don't re-use the crush washer once crushed).
 
Use whatever is supplied with the muzzle device. Or what's recommended by the manufacturer. The vast majority call for crush washers (with or without shims as needed). All the ones I've installed so far have used crush washers. I even ordered up some spares to have in case I needed to remove the muzzle device and then reinstall it later (you don't re-use the crush washer once crushed).

Mine came with both....looking for guidance
 
I will add, even though there are many Massachusetts people on this forum, that if you’re using a suppressor: DO NOT use a crush washer.

Also, don’t re-use crush washers.
 
I will add, even though there are many Massachusetts people on this forum, that if you’re using a suppressor: DO NOT use a crush washer.

Also, don’t re-use crush washers.

Got it jam nut if your gonna use a suppressor. Not planning on it but good to know.
 
Do you have a reaction rod or other method to hold the barrel so that torque applied to install the brake and crush the crush washer will only be applied to the barrel? If you are using clam shell on the upper for example, then don't use a crush washer. Without proper tools you are safer with a jam nut as application of torque is purely nut against brake.

With proper tools, the decision tree is as described above
 
Lmao no, shims only with silencers.
Or get the muzzle device that has external threads for the suppressor to mount with. Or ones that just ratchet on. That way the muzzle device doesn't get removed whenever you want to do the can can. ;)
 
Or get the muzzle device that has external threads for the suppressor to mount with. Or ones that just ratchet on. That way the muzzle device doesn't get removed whenever you want to do the can can. ;)

Thats what I meant, I just didn't say it very well. Plan B, Plan A and this new abomination of a taper mount from Dead Air don't need shims but the traditional QD mounts (ASR, Rugged, KeyMo) need shims if you want to time the brake, not important for a flash hider unless you want that perfect line up.
 
What do I put on the barrel threads. Grease or loctite?
What state do you live in?? If you're in the PRM (Peoples Republk of Mass) then you need to get it pinned and welded. If you live in Free 'Murica, then don't put anything on the threads. Leave them dry and hard. [rofl2] That's for the muzzle end. If you're talking about at the upper itself (under the barrel nut) then most people will put an anti-seize compound there. Or leave them dry and take the DGAF attitude. Depends on how often you expect to loosen the barrel nut. Most don't do that more than once or twice once setup. Maybe changing the handguard to something that uses a different type of nut. Such as the ones for free floating.
 
What do I put on the barrel threads. Grease or loctite?

If you want to secure it Rocksett is the best. A properly torqued muzzle device doesn't need Rocksett in my opinion but I have used it on a few occasions. If you aren't going to use Rocksett a little grease is cool.

 
Ok, so I have to ask, what is the reason reusing a crush washer is bad? I have reused a few (some of those multiple times even) with never a muzzle device coming loose.

Also, as for orienting the muzzle device, if it’s not where I want it to be, I have had good luck sanding some of the metal off the crush washer with an abrasive sanding belt and/or a grinding wheel.

Dave
 
Ok, so I have to ask, what is the reason reusing a crush washer is bad? I have reused a few (some of those multiple times even) with never a muzzle device coming loose.

Also, as for orienting the muzzle device, if it’s not where I want it to be, I have had good luck sanding some of the metal off the crush washer with an abrasive sanding belt and/or a grinding wheel.

Dave

It’s just what is considered best practice. The crushing part is what makes it tight and allows you to orient it to your desired alignment. If it’s pre-crushed then it’s not really doing that job. If it’s just a muzzle device I’ve reused a crush washer too, it’s low risk but not best practice.
 
Neither.
Peel washers and red loctite. That's how all builders who care about accuracy do it, if they use a muzzle device at all.

This. Peel washers are stupid easy to use and unlike crush washers will never crush.
 
This. Peel washers are stupid easy to use and unlike crush washers will never crush.

Peel washers for sure are the best choice. Red Loctite is just red water around 425 degrees. If your going to use an adhesive you may as well use Rocksett. It’s rated to 2000F or something silly, maybe even higher.
 
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