I’ll throw a monkey wrench into the conversation. 300WSM and 300WM factory 200gr Federal Terminal Ascents state 2810fps on the box. Turns out, that’s out of a 22” barrel. Guys I know are cronographing them at just over 2900fps+ with 24” barrels, and close to 3000fps with 26” barrels. I currently own a semi custom Kimber Classic in 300WSM and a Weatherby Mark V Deluxe in 300WBY. Yes, the WBY is about 100fps faster, but that’s minimal. IMO, the fact that the 300WSM is a short case, and they can be built around smaller guns, just makes them so much nicer to carry in the field than the WBY.
I get a solid 2980 fps average with the 200 grain Terminal Ascent out of my Nosler M21 24”. They wear a Shilen premium barrel. That was with a less than max load of RL26. I jugged one and it blew through seven one gallon jugs, retained an even 175 grains of weight and expanded to.708” diameter. I have yet to kill anything with it but I’m thinking it might work OK.
However, whatever a 300 Win Mag can do a Weatherby can do faster. That’s the whole point of Roy Weatherby’s artistry and when calculating energy velocity is squared.
KE= 0.5 x m x v2
