Why .300 Weatherby ?


Well-Known Member
Oct 15, 2007
Patagonia Mountains, Arizona
I'll play devils advocate by saying that I don't think the 300 Weatherby is all that popular at least compared to the 300 Winchester Magnum. "better" depends on how it's used.

Cartridge Length OAL capacity Pmax
300 WM 2.620" 3.340 95.5 grain* 62366
300 Wby 2.824" 3.560 98.9 grain 63817

With short bullets and "normal" seating depths the 300 Weatherby gives about 6% more energy resulting in 3% higher velocities for the same bullets. That's assuming you stay within SAAMI specs.

So what's "better" about the 300 Win Mag? it's case is 0.204 inches shorter than the 300 Wby. Typical "long actions" such as Rem 700 and Sako have 3.6" magazines. While that's a good match for the SAAMI length of the 300 Weatherby it does not have as much room for long low drag bullets which are desirable for long range shooting. The extra 0.2" makes a big difference in allowing the use of longer (not necessarily heavier) bullets and can typically deliver more velocity and energy at long range for the same weight bullets. Of course if you use an even longer (over 3.8") custom action that advantage returns to the 300 Weatherby.

*Several manufacturers make 300 Win Mag brass. They range in case capacity from 92 grains for Winchester to 95.5 grains for Norma.