The 17 Hornady Magnum Rimfire is a big success because of its slim appearance and its upgraded external ballistics. It was designed in 2002 by Littleman Mitchell of Hornady to produce rimfire cartridges that have unique flat trajectories. Several companies and bodies such as CCI, Federal, Hornady, Remington, and Winchester essentially manufacture the 17 HMR ammo.
Its parent case is .22 WMR and the bullet diameter is 4.5mm, a neck of 4.8mm, a shoulder of 6.0mm, and a base diameter of 6.0mm. The rim’s diameter is 7.3mm, and it is 1.3 inches thick. In total, the cartridge is 34.3mm long, including the 26.9 case length. 17 grained (1.1 grams) bullets cover 2,650 feet per second, and a 20 grained (1.3 grams) shell covers the distance of 2,350 feet per second; an excellent distance coverage indeed.
In appearance, the 17 HMR ammo does not have an oversized, thick look like the straight-backed cartridges; cartridges of this make are slimmer with more propellent force than most ammo.
The 17 HMR ammo promotes the accuracy, and it is suitable for hunting smaller-sized games like rabbits but is not restricted to small games alone; this ammo is perfect for medium and larger-sized games like deer and foxes.
Apart from game hunting, 17 HMR ammo in shooting sports, and because it is rimfire ammunition, it has low pressures (180.00MPa). Many hunters have begun using the 17 HMR ammo, mainly when they hunt minor games; the ammo's popularity has grown steadily because of its high ballistic performance.
The .17 Mach II (.17 HM2) is based off the CCI Stinger .22 Long Rifle (.22 LR) shell case that has the neck reduced to fit the .17 caliber. The .17 HM2 is a rimfire cartridge with 17 grain that has a velocity of 2,100 ft/s. The shell casing and bullet are designed to have a higher velocity than other caliber rounds in its class, so it costs more to produce than the .22 LR bullets but is still relatively inexpensive.
Designed in 2004 by CCI, Hornady, and Eley the .17 HM2 didnt receive as much attention as the previous .17 HMR. The .17 HM2 typically requires a modification of barrel change on most bolt action .22 rifles, and is not suitable to be placed in modified semi-automatic .22 rifles due to abnormal pressure changes on blowback they require. The bullet is designed to be lighter to give it the best possible maximum velocity, flatter trajectory, and longer effective range (Up to 160m) for small game hunting.
The .17 HM2 can be used on converted barrels such as the Ruger 10/22, but are harder to acquire due to lack of popularity. The bullet is designed to travel farther for small game hunters to hit targets at longer ranges while keeping the carcass meat salvageable for eating. At closer ranges the energy from impact can cause more damage and damage the majority of a carcass.
