Barrett M82A2
Barrett M82A2 -.50 BMG caliber.

Semi-automatic bullpup version of the M82A1 rifle.  The M82A2 was developed in the 1980's for the Afghanistan conflict.  Primary purpose was purportedly to engage low flying helicopters.

Status: Currently out of production

Vendor: Barrett Firearms Manufacturing

http://www.barrettrifles.com/

Barrett also sells two bullpup bolt action .50BMG rifles.  The Model 99 is a single shot .50 rifle, while the Model 95 feeds from a standard M82 magazine?.
Barrett M82A2 Bullpup .50 BMG rifle
Note the reversed M16A1 forward pistol grip
Proper firing position for M82A2 rifle
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