I felt like doing some loading this afternoon so I did up 50 rounds of the 245 grain MBC cast lead over 12.3 grains of H110. From earlier ladders, these should do roughly 1360 fps out of the 10.5" AR pistol. They make for a fun round to shoot. Kinda like chunkin bricks downrange.
I also did 20 rounds of 100 grain Hornady short jackets. (The jacket only extends about 0.25" up from the flat base). I have seen the postings where folks indicated they have gotten decent function in their AR with these & at less than $0.14 apiece, I wanted to try it myself. Hodgdon shows 18.8 grains as the starting point for H110 with 110 grain jacketed, with a max of 20 grains, so I used 19.0 grains for my test rounds. I seated them with only a sliver of the jacket exposed - with a COAL of 1.782", they are barely over the SAAMI minimum for loaded 300BLK ammo (1.780"). I'll have to get out to the range sometime this week & give them a try.
Nick
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