.17 Mach 2
.17 HM2
introduced in 2004
.22 Long Rifle case, necked down to .17 caliber (4.5 mm)
17 grains
Bullet weighs less than half the typical .22 Long Rifle bullet
.17 caliber bullet is much more difficult to manufacture than .22 LR
.17 Mach 2 typically cost twice as much .22 Long Rifle ammo
The .17 HM2 was never successful
(Visited 159 times, 1 visits today)