SAS Weapons - HK G36
Designed as a replacement for the German Army's main assault rifle, the G3, the G36 is a 5.56mm weapon that fires at 750 rpm. Made from tough polymer fibre plastics the G36 is both light and durable. The G36 uses a dual sighting system comprising of a 3x optical scope and a red dot reflex sight. With proper training, it is possible to quickly switch between both sights for close or longer range engagements.
Several variants exist apart from the full-size G36. The G36k is a carbine with a shorter barrel, designed for Special Operations forces such as the German KSK. An even shorter variant, the G36c, replaces the optical/red dot scopes with iron sights (although optics can be easily added to the weapon's rail). The G36c has been adopted by many Police forces worldwide, including several of the UK's armed response units. Further versions include the LMG36, a light machine gun with heavy barrel, bi pod and high capacity magazines. An AG36 40mm grenade launcher can be fitted to the full-size or K version.
It's reported that the SAS have used the G36k on operations in Afghanistan, although only in small numbers. 
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