Can I damage my AR-15 reciever while tightening muzzle device?

[[Pb]]

Hello,
I recently installed a Houge free-float tube on my Stag carbine, and afterwords when reinstalling the flash suppressor I notices that I really had to crank on it to get it tight and right-side-up, and I could see my reciever flexing a bit in the vice. It freaked me out so bad I left it with about a quarter turn till it will be on right side up, what should I do? I have sheared off buckets of bolts before by being a bonehead and overtightening, but no way I'm doing that to my AR... At this point I'm just to freaked out to keep cranking on it. Is it okay for my flash hider to be a little crooked? Am I just being paranoid about breaking the reciever?


Thanks!

 

[MrCleanOK]

If you have a directional muzzle device (there is a "top" and "bottom"), it should have come with either a crush or peel washer. The crush washer will compress to allow you to turn the device to the correct orientation, and the peel washer is laminated, and you remove layers to get the right muzzle device orientation (trial and error).

The BEST way to support your upper while you swap a muzzle device is with barrel block in your bench vise. This holds the barrel securely. You can also do the job with your upper in an upper receiver vise block, but that will transmit the torque of removing/tightening the muzzle device through the barrel, which can rotate the barrel assembly in the upper receiver if you really get to cranking on that muzzle device.

If you are working on your upper receiver WITHOUT an upper receiver vise block (a fixture that supports your upper receiver from the inside and out, and protects it from the loads of clamping) or barrel block, you need to stop working on that upper immediately until you get the right tools for the job. If you are flexing your upper receiver, you PROBABLY haven't done any permanent damage if you stopped immediately, but you need to get the right tools before you proceed.

 

[rskent]

Yep. You sure can.
Steve

 

[DMK]

The flash hider should be tightened to 15-20 ft-lbs, no more. Aside from potential damage, tightening a muzzle device too tight will also hurt accuracy. Also clamp the barrel in a vice, not the receiver. Use pine wood blocks to protect it from damage. As MrCleanOK said, use a peel or crush washer to orient it properly.

See Page 3-44

http://www.ar15.com/content/manuals/TM9-1005-319-23.pdf

 

[DougW]

+1 to what DMK said. I always use crush washers myself, and some anti-sieze on the threads.