.17 HMR (.17 Hornady Magnum Rimfire) is a small, very fast rimfire cartridge known for flat trajectory and precision on small game and varmints at extended rimfire ranges.

.17 HMR fires a tiny, high-velocity bullet that gives a remarkably flat trajectory and fine accuracy for a rimfire, making it popular for varmint and pest control and small-game hunting beyond typical .22 LR ranges. Recoil is negligible. Ammunition costs more than .22 LR and comes mostly in light varmint-type bullets, and it is not suited to larger game. It suits shooters wanting a flat-shooting, precise rimfire for varmints and small game.

General information about this caliber — not a recommendation for this specific firearm.