Seeing a lot of unburnt powder on the BCG, trigger group and even the buffer.

This is using Hornady 208gr AMAX in 300 BO.

New to suppressed rifles and wasn't expecting this.

Is it unusual?

Not sure about unburnt powder, but suppressed ARs push a lot of carbon / fouling back into the BCG, brass, top of the magazines, etc - excite amounts depends on the load, the weapon (how it’s gassed) and the suppressor, but it’s common.

+1 to Rhinoswo's comments. All DI AR systems blow a bunch of burnt powder back into the BCG area, and it's worse with a suppressor. Carbon fouling is just part of the beast.

IMO this is a primary reason people like piston systems, especially with cans.

Could be a filler and not unburnt powder. My 300 is covered with yellow specks all over the inside of the upper and lower. Been working through a case of S&B subs.

What's the velocity of the 208's in a .300 BO ? Just wondering.

quote:

Originally posted by redrider1596:
yellow specks

I don’t believe the load uses any sort of case filler. The natural color of smokeless powder is a sort of translucent yellow. It’s turned black by the graphite or other coatings that help it flow and meter properly.

quote:

Originally posted by Redhookbklyn:
Seeing a lot of unburnt powder on the BCG, trigger group and even the buffer.

This is using Hornady 208gr AMAX in 300 BO.

New to suppressed rifles and wasn't expecting this.

Is it unusual?

Nope.. not unusual at all.

Pistol length gas system, suppressed.... normal. Stay on top of maintenance/cleaning of the entire rifle and baffle/tube.

It is yellow in color.

Thanks all, appreciate the replies.

My 10" 300 BLK runs the 208, very accurate under 10.6 gr of 1680. Dirty yes, suppressed no powder left that didn't burn up. Head space a bit loose could maybe be the issue.

quote:

Originally posted by FN in MT:
What's the velocity of the 208's in a .300 BO ? Just wondering.

1020fps muzzle, 16" barrel, per Hornady.

quote:

Originally posted by Redhookbklyn:

quote:

Originally posted by FN in MT:
What's the velocity of the 208's in a .300 BO ? Just wondering.

1020fps muzzle, 16" barrel, per Hornady.

It appears the DDM4ISR has a 9" barrel and a suppressor. Figure the suppressor's effectively adding an inch or so to the barrel length for MV. Assuming 1020 fps in a 16" barrel, the DDM4 barrel likely produces MV of 940-970 fps. In theory.

quote:

Originally posted by FN in MT:
What's the velocity of the 208's in a .300 BO ? Just wondering.

From my ~17 inch T/C Contender barrel the 208 grain A-MAX load averaged 1036 fps muzzle velocity (a very limited sample of five rounds).

My only experience with short barreled 300 BLK is shooting one that a friend owns.

I didn't notice any unburnt powder with subs from his but I didn't clean it afterwards either.

8" with a SiCo Omega.



My 11.5" 5.56 pistol with a silencer doesn't exhibit any more fouling than the 16" 5.56 with silencer.


300 Blk is a different animal though so it wouldn't surprise me to see it behave differently.