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Have you noticed the lack of semiauto’s chambered for the .17 HMR? For a couple of reasons, mating the widely popular and super accurate .17 HMR to a semiauto, blowback action has proved to be a daunting engineering challenge. However, Magnum Research, the firm perfecting the gas-operated, semiauto Desert Eagle, has developed an innovative solution. It’s a gas-assisted, semiauto .17 HMR rifle, and it’s a dilly.

The .17 HMR cartridge is a bit persnickety. It’s a difficult cartridge from the viewpoint of pressure. The problem is not the level of the pressure. The cartridge functions well within SAAMI safety standards. The problem is the timing of the peak pressure point.

Almost as soon as the bullet leaves the case, the cartridge generates its peak chamber pressure, but the timing of those peaks is not consistent from one shot to the next. This peak pressure inconsistency has given engineers gray hairs when they set about to solve the mechanical timing and inertia issues inherent in a blowback, semiauto firearm.