View Full Version : New SIG 556 Rifling Imperfection

February 17, 2008, 08:40 PM
Hello all,

I just broke down my brand new SIG 556 to clean it out before heading to the range and I noticed that the rifling has a small scratch/imperfection in the rifling about 4 inches from the muzzle.

The scratch is not very deep, but is this something I need to bring to the attention of SIG, or just nothing? I know the barrell will get hot, and thought that this could be a weak point in the barrell that could later cause problems although I know nothing about the engineering/design of barrells on semi-auto firearms.



February 17, 2008, 08:57 PM
Shoot it and see how it groups. If you get shotgun patterns, something is wrong. If it puts them in nice little clusters, don't sweat it. I have a few very ugly bores that work great and the imperfection may be polished away after some use anyway if it is not too deep.

Jim Watson
February 17, 2008, 10:33 PM
Where is this imperfection in relation to the gas port?

February 17, 2008, 11:22 PM
Well, I don't have it in front of me, but I guess that if the imperfection is in the right spot, it is probably just the gas port. Good thinking!



February 17, 2008, 11:38 PM
Yeah, the gas-port will be something to watch out for.:D

March 6, 2008, 03:55 PM
Yep. That port bears watching all right. If it gets too big, the bullet will divert iself up into the gas port instead of out the muzzle and blow off your entire gas block. Very Bad JuJu.

March 6, 2008, 04:19 PM
Actually, there was a rifle with a removable gas block and a diverter...you took the gas block off and shoved the diverter in the barrel...the bullet would exit the gas port so you could shoot around corners....

Sort of like a krumlauf

WildfantasylandAlaska ™