300BlkTalk

Loading 130 grain SOST MK319 for 300 Blackout. Any suggestions for overall cartridge length. I am using H110 with Winchester small rifle primers. I have not range tested as of yet. Just loading dummies at different lengths and measuring to my
magazine. The length which measures the best is O.A.L. of 2.155 inches. Measuring some commercial loads they have been as short as 2.145 inches.

That bullet has been tried a few times over the years, I don’t remember anyone ever getting steller accuracy.

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I would start around 17.5 of 296 with bullet .010” off the powder and work it up with the same density, bullet powder relationship, to around 20 grains or pressure signs.