Steyr TMP is a modern compact SMG. It is blowback operated, locked breech design, with rotating barrel. This mean that after the shot bolt with barrel locked to it are moving backward for some 4 millimeters. Then, the barrel rotates clockwise slightly, and thus unlocks the bolt. Rotaton controls via small cam on the barrel that follows the spiral groove inside the receiver.
Both upper and lower receiver are made from polymer. TMP has no stock and could be fired only from off-hand position. Safeties featured automatic off-battery safety, drop safety and the manual safety switch. TMP is reported as a very controllable and comfortable to fire firearm.
The Steyr TMP (Taktische Maschinenpistole/Tactical Machine Pistol) is a select-fire 9x19mm Parabellum caliber machine pistolmanufactured by Steyr Mannlicher of Austria. The Magazines come in 15-, 20-, or 30-round detachable box types. A suppressor can also be fitted. The Steyr SPP is the civilian variant of the TMP which has no foregrip and is capable of semi-automatic fire only.
The Steyr’s trigger pull was extremely long (perhaps 3/4 of an inch) and somewhere between 17 and 20 pounds in weight. Each round fired was a test of will and strength between the trigger and the musculature of my finger, which I eventually won. The TMP’s sights are small, fixed and hard to use, although I did wring acceptable practical accuracy out of the gun with them.
In 2001, Steyr sold the design to Brügger & Thomet[ who developed it into the Brügger & Thomet MP9.
The Steyr SPP (Special Purpose Pistol) is a semi-automatic variant of the TMP. The TMP’s barrel and barrel jacket lengths were increased slightly so there is a greater length of protruding jacket and barrel. The forward tactical handle was removed and a small Picatinny rail installed on the forward handguard instead. It is somewhat large for a pistol and is constructed mainly from synthetic materials.
Caliber: 9x19mm Luger/Parabellum
Weight: 1,3 kg empty
Length: 282 mm
Rate of fire: 800-900 rounds per minute
Magazine capacity: 15 or 30 rounds