First, I suppose, it's important to list the contenders. Here goes, from the smallest diameter commonly available. I'd love to include all of the really obscure stuff, because it's so interesting and, in many cases, particularly capable, but if you can't find guns or ammo for it, well, it can't be in this article.
Peruse the following, weigh the options and hit us with your arguments.
This cartridge is the reason its littler sibling — the .17 Mach 2 — is languishing. Based on the .22 Magnum case necked down to BB diameter, it spits a 17-grain bullet out of the muzzle at 2,550 fps and packs 245 foot-pounds of punch. When sighted on at 100 yards, it drops 8.5 inches at 200 yards, making it a legitimate 200-yard cartridge — hold on a prairie dog'™s whiskers and you'™ll nail him in the belly button.
As a hot rod, it offers plenty of performance and is arguably more common on today'™s market than any other rimfire except for the .22 Long Rifle. It often produces jaw-dropping accuracy through bolt-action rifles. However, it has proven problematic in most semi-auto rifles. Granted, with today'™s ammo prices, few shooters purchase a .17 HMR rifle as a lead pump.
With careful shot placement, the .17 HMR is adequate for coyotes within 100 yards or so; it'™s ideal for beavers where legal, and makes short work of nuisance varmints such as skunks, prairie dogs and potgut gophers. However, unless you'™re rifleman enough to make head shots, it'™s not much of a meat-getter because that tiny, zippy bullet does considerable damage on impact. All things considered, many logical arguments can be made that it'™s the best rimfire for all-around hunting.
.17 Mach 2
The first really good cartridge that demands inclusion is the .17 Mach 2. Though sales undeservedly languished and few new guns are available anymore, it is a compact cartridge that offers a lot of performance. My esteemed colleague and veteran gunwriter, Layne Simpson, has said more than once he considers the .17 Mach 2 to be the best small game cartridge available, and Layne has filled more than one stewpot with rimfire-killed squirrels. It shoots tiny 15- to 17-grain projectiles at around 2,100 fps, providing well over 160 foot-pounds of energy at the muzzle. Because the bullets are bona fide jacketed numbers, it tends to shoot very accurately, too.
A flat trajectory and plenty of game-dropping punch — plus minimal meat damage — make the .17 Mach 2 a contender for that 'œBest Hunting Rimfire' title, non-popularity notwithstanding. If the rimfire world had a dark horse, this would be it.
.17 Winchester Super Magnum
Definitely the new kid on the block, the .17 Winchester Super Magnum
cartridge case is descended from concrete nail guns and has all the performance one might expect from such a heritage. Pumping a 20-grain bullet out of the muzzle at over 3,000 fps, it holds the title of the world'™s fastest rimfire, and 400 foot-pounds of muzzle energy doesn'™t hurt its effectiveness either.
Currently, only bolt action and single-shot rifles are being chambered for the .17 WSM. Early reports of extraordinary accuracy bode well for the cartridges future.
Only time will tell whether it will survive over the years, but there'™s no arguing that it'™s the flattest shooting, hardest-hitting, most effective — on bigger, tougher predators and varmints — rimfire in existence today. Though an argument rages between traditionalist supporters of the classic .22 Magnum and contemporary enthusiasts of the .17 HMR, there is no arguing the fact that the .17 WSM eclipses both of them with ease.
Though it'™s less than half the age of the .22 LR, this cartridge is still decades older than any of the others. Enthusiasts argue that it does everything that the .22 LR does, just better, and in some cases they'™re right. It costs more and doesn'™t function well through most semi-autos, but it hits harder and shoots flatter. Inside 100 yards or so, it'™s a better choice for coyotes and other predators than the .17s — with the exception of the .17 WSM, which is as yet unproven on the popularity scale.
Spitting 40-grain bullets out of the muzzle at close to 2,000 fps, the .22 Mag punches with well over 300 foot-pounds of energy up close. Less-than aerodynamic projectiles don'™t hold that energy well, but within its limits, the .22 Mag carries quite a lot of horsepower for a rimfire. Recent developments by Hornady have brought out a pointed, more streamlined 30-grain bullet that exits at 2,200 fps with 322 foot-pounds of energy. Sighted at 200 yards, it drops 16.5 inches at 200 yards — considerable, but a lot less than standard round-nose loads.
Many western government predator-control hunters use a .22 Mag for shooting trouble-causing mountain lions out of trees. A bigger caliber may knock the cat out of the tree, where the hunter'™s dogs will tangle with it, possibly getting clawed up before it expires. When hit through the lungs with a .22 Magnum slug, the lion just grabs onto the tree and holds on until it expires and drops — completely dead and harmless — to the ground.
.22 Long Rifle
Still holding the title of longest lived and most popular rimfire cartridge in the world, the classic, veteran .22 LR is without doubt the most versatile of all rimfires, and arguably the most versatile of all cartridges, period. With premium ammunition, a good match-quality rifle will shoot 10-shot groups the size of a runt pinto bean at 50 feet.
Almost all action types function and feed .22 LR cheerfully. Within reasonable ranges, it will kill any small game it'™s fired at, and with careful shot placement it'™s accounted for more than it'™s share of coyotes, badgers and other tough predator-type varmints. It'™s quiet, its recoil isn'™t even worth noticing, and for the most part, its per-round cost is dramatically cheaper than any other rimfire cartridge — before the recent ammo-shortage-induced buying frenzy, anyway.
Performance is modest: Most .22 LR projectiles range from 36 to 40 grains in weight, and exit the muzzle of a rifle at between 1,200 and 1,600 fps. Energy hovers between 110 and 180 foot-pounds for the most part — enough, but not excess. The most useful sight-in distance is 50 yards — if you stretch it much farther than that you'™ll shoot over the backs of a lot of bunnies.
The king of rimfires? Absolutely. You can argue others reach farther, hit harder and kill better, and you'™ll be right. But when the dust settles, there will still be 10 Americans shooting .22 LR for every one shooting the others. When it comes to honing skills, filling the stewpot and just having pure fun, the .22 LR smokes the others. And with that, my friends, I rest my case.