Buffman-RANGE
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Hornady Black 5.7x28mm Data Dump
🕑 Added 2024-02-27 14:33:46 +0000 UTCHornady is sending me 6 boxes of the Black as as well as the Critical Defense. I bought the 250 rounds for this testing from Patreon funds before I was able to get in contact with Hornady.
They are using their own brass. At least it is headstamped Hornady. There is some kind of coating on the brass. The brass is on average 56gr vs the 60gr FN. It holds about 12.8gr of water vs 12.0-12.2 that I got from the FN.
5.4gr powder charge, and we are meeting the BOX state velocities. On the same day we are seeing 170 fps improvement over SS197SR. Penetrations depths on the pistol and pdw are above the FBI Min. It is not a bonded bullet, so keep that in mind
The bad news 4 case neck separations. 3 in the MK57, which because of the RDB and nature of the BCG saved itself from exploding. However the AR57 upper I have does not have any OOB provisions, and the second round fed on top of the broken case neck, and subsequently KB! the gun. It held up very well and I have no injuries, but it's down for the count. AR57-Center is replacing the upper and they mentioned starting mid last year they have made changes to it's BCG to help prevent OOB firing.
We've had case neck separations in the FN brass before so this is NOT uncommon. We will need more rounds down range
Comments
Any time I had a separated neck on the p90 the hammer can’t fall on the firing pin
Any concerns about this going oob on the ps90?
At this point it's hard to say. I'm going to cut a piece of brass apart tonight and meausure the case wall thickness. Given that this coating is different than the factory, perhaps carbon build up from shooting suppressed is causing the cases to stick? The longer barrel guns (CMMG and AR57) are ones I shoot suppressed a LOT
Glad you are safe! Is the case neck separation only an issue in longer barrels? Or is it bad brass?
