I wonâ€™t go as far as to belittle the, uh, little .17 Winchester Super Magnum. Itâ€™s a unique cartridge that does what no rimfire has done before. Itâ€™s the fastest rimfire ever designed and actually performs spectacularlyâ€”for a rimfire.
What I will do is askâ€¦Why? The great charm about rimfires is that theyâ€™re versatile and inexpensive to shoot. The .17 WSM, superb distance performer that it is, is neither. While itâ€™s capable of perforating a prairie dog farther away than â€ścommonâ€ť rounds, such as the .22 Magnum, most savvy shooters have transitioned to centerfires when distances stretch that far. And up close the .17 WSM is actually going too fast: Squirrels and cottontails suffering a body shot from it leave the hunter with little but fluff.
By stew-pot decree, any rimfire not well suited for small-game hunting is, well, not really a rimfire. Itâ€™s an outcast. What some folks charitably term a â€śnicheâ€ť cartridge.
Contrast that with the .22 Magnum. While itâ€™s not as aerodynamic as its .17-caliber sibling, it hits authoritatively within the rimfireâ€™s realmâ€”inside of 150 yards or so. For small-game hunting, full-metal-jacket projectiles minimize meat damage; likewise valuable pelts about to be separated from their host furbearer. Butchers effectively use a .22 Mag pellet between the eyes on even the biggest steer.
Government trappers prefer it for killing troublesome mountain lionsâ€”cats die in the tree instead of being knocked out, hurt and fighting mad, into their pack of valuable dogs.
And, finally, even homeowners have viable ammunition choices engineered specifically for self-defense to choose from. If thatâ€™s not versatility, what is? â€”Joeseph von Benedikt
Hunters need just two rimfire cartridges for small game: a .22 LR if they want to eat it and a .17 Winchester Super Magnum (WSM) if they wish to kill it. The .22 Winchester Magnum Rimfire (WMR) splits the difference between the two, crushing them both in all the categories that donâ€™t matter.
The .22 WMR fires a projectile too fast for use on tablefare, such as squirrel or rabbits. Whatâ€™s more, the bullets are ballistically inefficient at longer range. See for yourself. With only a 5 mph breeze, Hornadyâ€™s .22 WMR 30-grain V-MAX drifts 6.9 inches and strikes with 94 ft.-lbs. of energy at 150 yards. At that same range, Winchesterâ€™s .17 WSM 20-grain load drifts only 2 inches and carries an impressive 230 ft.-lbs. of energy. At 200 yards, where the .22 WMR is running on fumes, the .17 WSM is still scooting right along and carries twice the energy of the .17 HMR, itself a long-range rimfire.
What about bullet weight and penetration, two attributes the .22 WMR does possess? They simply donâ€™t matter on game that can fit inside your motherâ€™s purse. What about coyotes? Skip both and use a centerfire.
However, if you must use a rimfire on predators, opt for the 25-grain .17 WSM load. Using its superior velocity, the .17 can and will knock down any coyote within 150 yards as long as you hit your mark. Youâ€™ll be surprised at the long-range killing power of this little thumper, and youâ€™ll save a few bucks in the process.
Speed kills, and the .17 WSM slaughters the .22 WMR in velocity, trajectory, wind drift, and retained energy. Its rimfire lethality is far superior to anything stamped â€ś.22 WMR.â€ť â€”D. Faubion