Re: 458 SOCOM Load Data
Using Reloder-7, Remington 2 1/2 Large Pistol primers, Starline brass trim 1.570", Hornady 325gr FTX for an OAL of 2.197", 40.0 gr gave me about 1765fps out of a 16" RRA barrel...
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eta: H110, H4198, and Lil' Gun are favored powders atm, Lil' Gun and H110 are going to give you higher velocities but I got like 6# of Re-7 to go through first.