So... friend of mine that was helping me with some load development for .358 Winchester... took some cheap blem #3510 Hornady's and some BS Amerc Powder... 7.62 Military brass (necked out to .358)...
On a Green Mountain cheapo .358 blank on a RR Remington 700 action and 3-9 Cabelas scope did these three at 100 yesterday...
Most of the .358W loads are running hot and fast with these pills with IMR-3031 and BL-C(2)... up to 2,640 FPS
These three were slow... only 2,240 FPS.
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Why is any of the this relevant to .357 AR?
Same blanks (1:14 twist) and same pills... and similar speeds (maybe)... and a 20" barrel.
Been working on a idea called "Barrel Time Theory" with QL... i.e. cross-compatibility of various powders based solely on barrel time.
FYI... the load above was purely a blammo load for my .358W (i.e. speeds are 400 FPS slower than my .358W hunting loads).