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MAST 300 blackout brass

Choid

Anti Bodyfat Activist
Full Member
Minuteman
Feb 13, 2017
5,373
3,615
I just came across a couple thousand of these cases in my shop and wanted to know if anybody had intel on them. I've been using Starline, and don't know the case capacity difference, or whether the MAST stuff is garbage. I'm not close to a hot load, and Starline generally has low water capacity, so I can probably figure this out relatively quickly, but any additional info is really appreciated.