KyBigGunKy,
Welcome to the 'fire. I have something close to the .375 Wea. It is a .416 Rim Mag necked down to .375 with a 28" barrel. Here are some loads:
Nosler 260, H4350 @ 99.0 = 2,950 feet per second
Barnes 270, H4350 @ 88.0 = 2,870
Barnes 270, IMR4320 @ 83 = 2,950
Barnes TTSX 250, IMR 4320 @ 84 = 3,000
These are maximum working loads with no signs of pressure to me. The 250's generally grouped between 3/8" and 3/4" at 100 yards. The 260's and the 270's were 1 - 1 1/14".
That's
eleven grains higher than what Hodgdon shows as a 53KCUP top load.
