I need to rethink my 7.62x39 loads.

[CoalCrackerAl]

I did a scope swap on my AR 15. And shot the loads with .308 bullets. After awhile i started to get a lot of soot on the cases. Not just the neck. But down the whole side of the casings. I also loaded 5 with the .311 bullets. I shot them at 100 yards after i got the scope zeroed. They shot fine. Im going to load up 40 rounds with the .311 and see if i get the soot after the rifle warms up. Other than that i had fun nailing the steel. I put my Vortex strike eagle on it.

 

[stoney1666]

my AR loves 150 gr 311 bullets.

 

[troy fairweather]

May just need a heavier buffer or spring or adjustable gas block.

 

[CoalCrackerAl]

I looked up the buffer spring info. It shows an h rated one vs s for 223/556. My lower is a PSA Multi caliber. I'll back my load off some for now. I did load the last rounds 2 grains higher than before.

 

[N555]

Lots of things cause soot covered brass.
Light loads, over pressure (usually in straight wall cases), loose chamber, using a silencer on a semiauto or any condition in a semiauto that will cause it to not have enough dwell time.

 

[CoalCrackerAl]

I loaded some .311 with the starting charges i used in the past. And some with the same loads the .308.I hope i can get out today and test those. I did change the muzzle brake too. It's one with a blast can. Like in the pic,

 

[N555]

Isn't a "blast can" just a flash hider with one baffle?

 

[CoalCrackerAl]

Here it is apart. I do think the flaming pig ones have a baffle.

 

[CoalCrackerAl]

Well i tested with the .311 bullets. Still got the soot. So i think it's my new muzzle device. I'll put my sound forwarder back on. One thing interesting. The lower power loads grouped good. The ones with 2 more grains the groups opened up.

Could it be the new starline brass?