Upper and Lower Receiver
The upper receiver is made from anodized aluminum forgings, and is non-stressed. It features a non-reciprocating charging handle on left side which also acts as a forward assist.
The quad rail system is integrated into the upper receiver and compatible with most 1913 Picatinny devices. The top rail is monolithic and 17” long, providing a rigid, uninterrupted plane for mounting optics and BUIS (Backup Iron Sights); the 3, 6, and 9 O'clock Position Rails are 8" long.
Read more about this topic: Robinson Armament XCR
Famous quotes containing the words upper and/or receiver:
“Surely you wouldn’t grudge the poor old man
Some humble way to save his self-respect.
He added, if you really care to know,
He meant to clear the upper pasture, too.”
—Robert Frost (1874–1963)
“Flattery corrupts both the receiver and the giver.”
—Edmund Burke (1729–1797)