.223 WSSM

Introduced in 2003 by Winchester and Browning, the .223 Winchester Super Short Magnum (.223 WSSM) emerged as a unique addition to the short magnum family. Based on the concept of maximizing case capacity in a compact envelope, this cartridge was designed by necking down the .300 WSM case to accept .224” bullets. The result was a high-performance, high-velocity cartridge aimed at outperforming traditional .22 centerfires like the .22-250 Remington and .220 Swift. The creation and marketing of the .223 WSSM capitalized on the early 2000s trend toward short, fat cases that theoretically burn powder more efficiently, thus delivering superior ballistics in lighter rifles with shorter bolt throws. While it generated considerable interest upon release, its specialized design ultimately limited its widespread adoption.

For ammunition reloaders, the .223 WSSM offers an intriguing platform with applications rooted primarily in varmint and small game hunting, as well as certain competitive shooting disciplines. Its flat trajectory and blistering speed make it particularly suitable for long-range varminting, where precision and minimal bullet drop are paramount. Enthusiasts keen on reloading gravitate to the .223 WSSM for its ballistic advantages but also for the challenge and satisfaction associated with loading a less-common, high-pressure cartridge. In addition, its unique case dimensions—wider and shorter than most—provide a different reloading experience in case prep, neck sizing, and powder measurement. Shooters seeking a high-velocity .22-caliber option for prairie dogs, groundhogs, and other small varmints find the .223 WSSM’s performance hard to match among factory options.

The primary target species for the .223 WSSM are small to medium-sized varmints and predators. Ground squirrels, prairie dogs, and woodchucks are classic examples where this caliber’s speed translates to accuracy and immediate results, even at extended ranges. Coyotes and foxes also fall well within the effective reach of the .223 WSSM, especially where shots may exceed 300 or even 400 yards. The cartridge’s velocity allows for highly effective expansion of varmint-class bullets, making it a favorite for hunters looking for clean, rapid dispatch of pests. While theoretically capable of taking small deer with appropriate bullets and precise shot placement, most hunters and reloaders prefer to limit its use to varmints and predators, both to maximize barrel life and due to better-suited medium-game cartridges on the market.

Typical bullet weights for the .223 WSSM range from 40 to 64 grains, although the sweet spot for reloading is often found with 50 to 55-grain bullets, which exploit the enormous velocity potential of the cartridge, commonly achieving muzzle speeds of 3,800 fps or even more. Heavier bullets, such as 60- or 64-grain projectiles, can be used for slightly larger game or for improved wind-bucking abilities at distance but may sacrifice some of the signature speed. The .223 WSSM’s high working pressures and relatively overbore nature mean reloaders should exercise caution and consult current load data to avoid excessive throat erosion or pressure spikes. Brass availability can be a challenge due to discontinued factory support, making case care and occasional annealing key for longevity. For precision-oriented reloaders who appreciate ballistic performance and don’t mind the quirks and extra effort, the .223 WSSM delivers impressive results in the field or at the bench.