Contaminated Brass

[Ishallbie O'Cullkillin]

Just got done with a 2k batch of converted 300blk brass. During load testing with a new gas system, upper & bolt & carrier, I have been getting occasional severe overpressure/overgassed signs. The load is a known moderate/high end load that functioned well before the component swap. The new converted brass is a new variable. I've narrowed it down to either too light of a buffer, or the conversion brass, which was made from pulled .223 ammo with Data74 powder in it, still may have powder residue in it that is contributing to the pressure spikes. Is there a solvent that I could put on a swab & clean out the new brass without hurting primer performance?

 

[armorpl8chikn]

Re: Contaminated Brass

Powder residue? Tumble the brass and that won't be an issue. But you left the primers in there from the pulldowns. Frankly there is a laundry list of problems loading ammo in the manner that it appears you are practicing. If I were you I would back the load down, cause tumbling with the primer in there is possibly safe it is possible that it could affect primer performance. Tumbling media tends to get in some pretty tight places and may cause a hangfire if tumbled.

A dry swab should knock the powder residue out. If you can't see powder kernels that isn't your problem.

 

[Ishallbie O'Cullkillin]

Re: Contaminated Brass

Thanks for the reply. I tumble 10k cases per year, and am sick of picking media out of flash holes, so that's not an option. I just looked through 150 prepped cases & found 13 of them with 1 but no more than 3 granules of residual Data74 powder. I will blow compressed air through the remaining cases, change to a heavier buffer, and consume a small amount of a high grade alcoholic beverage.