Winchester released their .300 Winchester Short Magnum cartridge to hunters in 2001. The .300 WSM is part of a group of short magnum cartridges that Winchester released in the first years of the new millennium. Hunters, for the most part, welcomed with a positive response these new cartridges, as they offered improvements upon existing legendary cartridges with updated case design, cleaner burning powders and optimized bullets.
The bullet of the .300 WSM is 0.308 inches in diameter, and case dimensions are similar to many other .308 caliber cartridges. The .300 WSM, therefore, as other cartridges in the line of Winchester Short Magnum cartridges, will function in a rifle with a short action. Short actions cycle easier and faster, an added benefit for shooters of smaller stature. The immediate visible difference compared to the original magnum cartridge is a sharp shoulder angle of 35 degrees and the generally shorter and wider appearance of the cartridge. The shape offers the advantage of a more efficient powder ignition and burn. Greater powder burn efficiency means less powder is required to obtain the same performance, and therefore, the cartridge generates less recoil - all due to the shape of the case.
The .300 WSM performance numbers mimic those of the .300 Winchester Magnum, the cartridge after which it was modeled. It does not hold as much powder, yet is able to harvest all medium and large game animals in North America at long range, including elk. Soft Point bullets weighing 150 grains leave the muzzle at 3,100 feet per second and carrying more than 3,600 foot pounds of energy. Hollow point bullets weighing 180 grains leave the muzzle a little slower at 3,050 feet per second, but they carry more than 3,800 foot pounds of energy. Bullet options include Trophy Bonded Tip, Fusion bullets and Power Point bullets, providing hunters with many choices for just the right combination of bullet weight and bullet design for their exact needs.
The .300 WSM provides great performance from a shorter cartridge and a shorter action. More shooters can use rifles that fire this cartridge with greater comfort and speed. The case design provides the same high performance of the original larger cartridges, but with lower recoil. Finally, since being accepted by the market, many manufacturers are producing many types of ammunition and giving shooters the ability to select the perfect ammunition for their needs.