$1699.00 for something that does that to the brass? Looks like it is a piece of junk............
PISTOL, BANSHEE, Mk10, 10MM, 8" | CMMG - AR 15 and AR 10 Builds and Parts
There is something seriously wrong going on here. Your gun has an oversized chamber, or your dies are out of spec, or both. Google "Hogan's goat". DO NOT RE-USE THIS BRASS. A "Bulge Buster" would make the brass look good again, but the damage has been done and is permanent. Flatten the brass so it can't be used again, and then recycle it.
Get new brass after you figure out the source of this dangerous situation.
You obviously haven't had any experience firing (+P) pistol caliber cartridges in AR platform pistols/rifles.
They all have the same problem, from what I've read, seen & experienced, because of the AR style rifle bolt used which differs from a breech locked pistol's slide & barrel/chamber enclosure.
It's a well known problem, documented across many brands, & it's cause is similar but different than the well publicized Glock smiles.
While these were hotter loads than standard published max charges these same loads in fully supported chambers do not bulge.
Factory loads that I've shot (most of which are weak) or moderate handloads won't bulge in the unsupported AR barrel/chambers.
Because too much of the head of the brass has nothing to support it in an AR style bolt, & unlike rifle brass which has very thick brass above the web, the brass between the AR bolt face & the chamber is only supported by the brass itself.
Completely different than found in typical pistols.
9x19 brass has much thicker brass above the web than 10AUTO has & consequently it's far less prone to bulging in an AR style pistol/rifle but if you push them (& I have) they'll start to bulge too, just a lot later.
And it's not isolated to the CMMG Banshees. My son has Kriss Vectors in 9x19 & 10AUTO & we both have Freedom Ordinance FX-9s, all AR style bolts which result in the same flaws with pistol caliber cartridges.
No, it's not good advertising for this style gun but it is what it is. You just have to shoot the appropriate loads in them or they'll bulge so using the "slightly" stronger brass option helps, a little.
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CMMG Banshee MK 10, 8" bbl
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