IWA 2017 - The Austrian Steyr Mannlicher company showcased the STM 556 assault rifle, now an entrant for the new German rifle trial
The gun enthusiasts and military communities are now very fond with the Steyr Mannlicher STM 556 assault rifle – a proprietary Austrian take on the most quintessential American assault rifle.
At the 2017 edition of the EnforceTac – a side event of the IWA OutdoorClassics expo, dedicated chiefly to military and law-enforcement oriented products – Steyr Mannlicher showcased the rifle at a moment when a variant of this rifle manufactured jointly with Rheinmetall, and dubbed the Rheinmetall-Steyr RS556, is taking part to the "System Sturmgewehr Bundeswehr", the German Armed Forces trial that will select an advanced weapon system to replace the currently-issued Heckler & Koch G36, with first deliveries slated to start in 2019.
The STM 556 is Steyr Mannlicher's own take on thre AR-15, with one chief difference from which all others spawn: the short-stroke piston-driven, adjustable gas system is just the same as the one used in Steyr's own, highly successful AUG bull-pup rifle system.
The Steyr Mannlicher STM 556 fires the 5,56x45mm NATO cartridge and feeds through standard AR-15/M16/M4-type magazines.
Steyr Mannlicher issues clear polymer magazines that are STANAG 4179 compliant (e.g. compatible with all AR-15 type rifles) and patterned after the Steyr AUG's "waffle" magazines. Other features include a six-positions collapsing stock, a railed upper receiver and handguard, and fully ambidextrous controls.
Barrels for the Steyr Mannlicher STM 556 are cold hammer-forged, and sport the same quick-detach system as those of the Steyr AUG; this means that they can be easily removed and swapped with another in a matter of seconds, with just the push of a finger, with no tools required, and without loosing accuracy thanks to the fixed trunnion.
A number of standard barrel lengths are available (14.5", 16", 18" and 20"); however, customer-specific barrel and rifling lengths can be easily created. A special breech system with an emergency operation feature ensures that the weapon always functions reliably even in extreme operating conditions, such as in severely hot and cold environments.