The original standards for the .400 Jeffery were 60 grains Cordite and a 400 grain bullet at 2125 fps in a 30" pressure barrel for 16 tons bolt thrust. In rifles with 24" to 26" barrels, Cordite ammo was well under that.

My understanding is that Butch does something completely different with this cartridge. Seems like I read somewhere that his load gives 2150 in a 24" barrel - much hotter than the standard load. You should ask Butch for the load that he regulates with.

In my 26" barrels, I've used anywhere from 68 to 70.5 grains Reloder 15 (due to lot to lot density variance) to get 2075 fps with 400 grain Woodleighs. I use new Bell brass and Federal 215 primers.
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