Well went and did a little testing with the 300blk today. Shot 4 different loads, the Ozark 110gr hp and 147gr fmj, Remington 120gr OTFB, and that Barnes stuff.
Using nothing but a sandbag I can put every round in a 2" circle at 100, with each ammo. Using a rest that holds that whole gun, the 110gr is at about 1.5", 147gr at 1.25", barnes is at 1", and the Remington at 1" also.
Had 2 failures to feed with the 110gr hp in 60 rounds. The overall length on these rounds is extremely short and I think is the sole reason for the malfunction. I've had 0 failures with anything else. Pic of the size difference below. 110gr hp vs 110gr Barnes
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