So I have a SR15 MOD 2 that I absolutely love. It shoots wonderful and has had ZERO issues in its first 550 rounds. However I’m noticing this on the gas tube.
It’s along almost the full length of the tube. I did spray ballistol on the barrel and gas block and cleaned in there with a pipe cleaner and some q tips between range trips. Is that black marks just that oil and crap burning off. I shot 150 rounds today in about 20 minutes and some mags I ran through it quickly and the gun got very hot.
If it’s purely an authentic issue then no big deal it’s a tool and I still love it. I just want to know if there’s anything to be concerned about. Thanks for your time.
Nope. I wouldn’t be concerned at all. Looks like residual burn-off to me. As long as it’s not affecting the function of the rifle I’d just keep shooting. Knights has great customer service, so I know they’ll take care of you if there’s a problem.
For clarification: what, if anything, did you put on the tube before firing?
Was the factory oil removed?
If you put anything on the tube, did you remove the factory oil first?
From Tapatalk:
Jack Leuba
Knight’s Armament Company: Military/Govt Product Liaison
F2S Consulting: Director of Shooting Stuff
The first range trip I put nothing on the rifle. After that I noticed some brown marks on the gas block. I sprayed ballistol on the gas block and barrel and wiped off what I could with q-tips. I knew the excess would burn off on my next range trip so I expected some smoking when the gun got hot but I did not expect the markings. I’m guessing it’s the excess ballistol and possibly some cotton from the q tips causing the marks.
Is it of any concern? I don’t see it hurting the function or the durability of the rifle.
My MOD2 upper has about the same round count as yours and the gas tube is still nice and shiny. My guess would agree with yours that it’s probably the ballistol.
Ballistol has petty low burn point.
Thinking that the mix of oil and ballistol reacted poorly to the high heat of the tube. I’d recommend ballistol only in low heat uses. Can’t think of an area where a decent CLP or modern non-toxic high heat lube wouldn’t be better when applied to the AR platform.
From Tapatalk:
Jack Leuba
Knight’s Armament Company: Military/Govt Product Liaison
F2S Consulting: Director of Shooting Stuff
I use MPRO7 on all the moving parts. Ballistol more as a cleaner. Couldn’t get the MPRO7 in there past the rail. As long as it doesn’t hurt anything I’m ok with it
