The Steyr Tactical Machine Pistol or abbreviated Steyr TMP belongs in the emerging group of “Personal Defense Weapons” – short, stockless, and closer to being an enlarged pistol than a down-sized submachine gun. Indeed, a variant model which does away with the front handgrip and only fires single shots is called the “Special Purpose Pistol” (SPP) and is classed as a pistol.
The Steyr TMP is a locked-breech weapon firing the 9 mm Parabellum cartridge. There are only 41 component parts, and the frame and top cover are made from a synthetic plastic which is sufficiently strong to be able to do without steel inserts to support the bolt. The breech is locked and unlocked by rotation of the barrel, a system which Steyr pioneered in the early years of the century but which they ceased to use after 1918.
A lug beneath the barrel engages in a groove in the frame. On firing, the barrel and breech block recoil still locked together, the lug sliding down the groove. The groove then spirals, and as the cam follows this track, so the barrel is revolved until the bolt lugs are unlocked from the chamber. The barrel is then held while the bolt runs back and then forward again to chamber a fresh round. Bolt and barrel then go forward, and the cam track again revolves the barrel to lock the breech.
Single shots or automatic fire are provided by a two-stage trigger, similar to that used on the Steyr AUG rifle. The first pressure on the trigger fires single shots; pulling through against the pressure of an auxiliary spring delivers automatic fire. There is a three-position cross-bolt safety catch which has a central position giving semi-automatic fire only, so providing additional control.
Although there is no butt-stock, and no provision for fitting one, the forward handgrip permits adequate control of the weapon, and short bursts can be fired with considerable accuracy after a little practice. Single shots can be fired with one hand quite easily; it is only slightly heavier than a Colt .45 automatic pistol and somewhat lighter than most larger caliber revolvers.
Initially made in 9 mm caliber, production in .40 Smith & Wesson caliber has now begun, and there are plans for a modular system of interchangeable parts which will allow the TMP to be converted to fire 9 mm Steyr, 10 mm Auto or .41 Action Express cartridges.
Technical specifications of Steyr TMP (Tactical Machine Pistol)
|Manufacturer:||Steyr-Mannlicher GmbH, Steyr, Austria|
|Type:||Recoil-operated, selective fire|
|Caliber:||9 mm Parabellum|
|Barrel:||5.12 in (130 mm)|
|Weight (empty):||2.86 lbs (1.3 kg)|
|Magazine capacity:||15 or 20 rounds|
|Cyclic rate of fire:||600 rounds per minute|