Is it possible to rotate the barrel of an m400 predator (20 inch barrel) 180 degrees ?

somehow the local gunsmith installed a muzzle break upside down. since I live in nj it had to be pinned and welded.
I was thinking that if it is possible to just rotate the barrel it might be better than having them try to remove the brake and put it back on the right way.

I have never had it apart an figured the guys on this forum would know for sure if it can be done. Is there any difference in the barrel ? ports/holes/pins.... that would prevent you from just rotating it 180 and reinstalling with the break in the correct position ?

Thank for any help you can provide

Yes, your gas port is drilled in the top of the barrel and you've probably got feed ramps cut into the chamber end.

To say the least, drilling the pin on the brake is your easiest course of action.

If you check out a bare barrel, like this one ( https://www.rainierarms.com/ra...16-rock-creek-blank/ ) you'll see some of the features that are specifically oriented even before you put a gas block on.

I figured as much but was hoping it would be easy.

Thanks for the info

The feed ramps are on the barrel extension, which is technically a seperate part from the barrel, but its torqued on so tightly that hardly anyone ever removes it. Add the the barrel index pin to the gas port in the list of reasons why it isn't practical to rotate an AR barrel 180 degrees.

If you absolutely positively can't get the brake off, I'd either get a new barrel, or cut the brake off and rethread the barrel. And make the doofus that installed the brake upside down pay for it.

quote:

Originally posted by Dwill104:
the doofus that installed the brake upside down

This is exactly the sort of thing I think about whenever I hear someone refer to “professional gunsmiths” and ridicule the “amateurs.”

I'd say that gunsmith owes you a correction, or a new barrel, muzzle brake, and a refund, and he can keep his F-up.