The STM-556 assault rifle was first introduced in 2012 by renowned Austrian gunsmith Steyr-Mannlicher. It was announced in 2016 that the rifle would enter the Bundeswehr competition to replace the then-in-service HK G36 rifle.
To participate in this competition, Steyr-Mannlicher cooperated with Rheinmetall, another well-known military company. Your entry explicitly specifies RS-556 (for Rheinmetall-Steyr).
The STM-556/RS-556 rifles represent an attempt to combine the ergonomics and layout of the now ubiquitous American M4 carbine with some of the other advances of their own famous Steyr AUG-77 assault rifle function combined.
As such, this weapon uses the same basic layout as the M4 carbine, with a two-piece receiver made of aluminum alloy and connected by two cross pins. The controls are also similar to the M4, except in this case they are fully ambidextrous.
The main difference between the STM-556 and the standard M4 carbine is the gas system and barrel receiver interface. The barrel of the STM-556 is quick detachable with an exchange system based on the proven Steyr AUG.
Replacing the barrel requires no tools or disassembly and takes less than a minute. The gas system is also based on the Steyr AUG with a manual gas regulator with a short stroke gas piston.
Year of Service
2012
Origins
Austria
Categories
Assault Rifle/Assault Carbine
Steyr-Mannlicher - Austria / Rheinmetall - Germany
Austria; USA
Auto function
Has mechanical features to automate the firing process.
Assault Rifle
A modern class of long guns with selected fire characteristics, automatic internals and magazine feeding.
Overall Length
850mm
33. 46 inches
Barrel length
370mm
14. 57 inches
Cured weight
6.33 lbs
2.87 kg
Attractions
Front and rear irons; optional optics
Selective fire; gas powered
Gas Power
proposes a pneumatic system that typically consists of a cylinder and a rear drive piston that directs power to the bolt assembly.
Caliber*
5. 56x45mm NATO
Circle/Feed
Removable 30-round magazine
Maximum efficiency. Arrived
1,650 feet
(503m | 550m)
Rate of fire
900
Number of revolutions
Mile speed
2,900 ft/s
(884m/s)
STM556 - Name of the basic series RS556 - Assault rifle form offered by German Rheinmetall and Steyr-Mannlicher; variable barrel length; 4. 2kg weight; adjustable optical axis; standard and optional Optional accessory rail bracket.