The ADCOR Defense BEAR (Brown Enhanced Automatic Rifle) is a very nifty new piston-operated AR-15 carbine. The piston is permanently attached to the bolt carrier (think AK-47) and it travels through a machined boss in the upper receiver, which prevents the problem of carrier tilt. The BEAR includes both the standard AR-15 rear charging handle and a forward, folding and non-reciprocating charging handle.
The 14.5″ barreled model weighs 6.85 lbs and the 20″ model weighs 7.80 lbs. Barrel lengths available will be 10.5, 14.5, 16.1, 18 and 20″
The BEAR will go on sale later this year.