Now remember Chaps... No pew, then pew and finally pew, pew, pew :-)
|Picture credit: Facebook Page - Anti Poaching and Wildlife Protectors|
The firearm in the picture is the M4 Type Carbine (assault rifle) - manufactured by Bushmaster Firearms International. It is modelled on the AR-15 platform and is thus compatible with most standard AR-15 parts, including the ability to accept all AR15/M16 type NATO magazines.
Although there are versions that fire in full-automatic mode, I presume - in this case the firing selector is marked 3 x ‘pew’ as in this position it allows for three-round bursts with a single pull of the trigger (to save ammo).
Calibre versions include: .223 Remington, 5.56x45mm NATO, 6.8 mm Remington SPC, and 7.62×39mm (Soviet).