Q: Ive been thinking about buying a .30 magnum for all of my deer and big game hunting, but I’m undecided which one to buy – the .300 WSM or the .300 Win. Mag. I like what you’ve written about your Model 70 Winchester in .300 WSM, but you’ve also heaped praise on the larger .300. Can you tell me what the advantages and disadvantages of the .300 WSM are? Why you prefer it?
A: Let’s get right down to it! The .300 WSM packs the velocity and energy of a standard belted magnum case into a compact little cartridge that functions through a light, short action, mountain rifle. And because of the efficiency and design of the short, fat case it produces magnum velocities in a 610mm barrel with less powder and recoil. As I’ve found in the last dozen years, the family of Winchester Short Magnums in .270, 7mm, 300 and .325 put out in the Model 70 Classic action are sensational performers in the field. The first was the .300 WSM which has a case length of only 53.34mm, a maximum overall cartridge length of 72.64mm, a 35 degree shoulder and useful 7.566mmm neck and a head size of 13.59mm. Despite its short length, the cartridge was designed to offer the same ballistic performance as the .300 win. Mag., and indeed it does. It didn’t take much work with the .300 WSM before it became apparent that the short, squat powder column in the sharp-shouldered case offered ballistic benefits that could be verified with a chronograph. My rifle handles all bullet weights from 150 to 200 grains, but is probably best suited with a premium grade 180gn bullet which leaves the muzzle at 2970fps ahead of either 65gn of W-760 or 71gn of Re-22. My rifle has a laminated wood stock, wears a 3-9×40 Zeiss Conquest in Leupold Q/R mounts, and has an all-up weight of 4kgs. It groups sub-MoA and packs a big punch being the ballistic equal to the.300 WSM. Other advantages are: less muzzle blast and moderate recoil when compared to its full-size belted equivalent.