For all the the AR platform lovers who have seen just a small number of different configurations we have posted on this site here is another.
The FN P90 changed the design of their magazine to be on top of the weapon to keep the rifle in a small neat package to be a PDW but still allow for a large number of rounds to be loaded in the weapon.
The AR-57 upper simply replaces the standard 5.56/.223 upper and since the magazine is top mounted like the FN P90 keeps the weapon small while having the ability to to hold up to a 50 round magazine and not have a long magazine protruding from the weapon.
The magazine is the same as on the FN P90, depending on state and local laws for magazines modified magazine are available in 5 and 10 round set up.
The Carbine 16” barrel set up weighs about 7.45lbs. unloaded and just over 8.5lbs loaded with a 50round magazine.