I had a .375 WCF in a Ruger No.3 carbine. I used 220-grain Hornadys over 38.0 grains of AA1680 for 2285 fps and about 1.5 moa accuracy. The 200 Sierras were faster of course, 40.0 grains of AA1680 giving 2495 fps an 2 moa. AA1680 gave me higher velocities and better accuracy than Reloder 7, which is the "classic" propellant for this case. As always, work up from below.
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