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Upper Receiver Groups


All of our 6.8 x 45 UCC complete upper receiver groups feature barrel assemblies with military specification chrome lined bores and chambers and come standard with phosphate finishes. Standard AR Semi auto bolt groups feature industry standard high pressure tested bolts that are magnetic particle inspected. The upper receivers are made to military specifications for tolerances, fit and finish, as such they will easily attach to lower receivers that are of the same specifications.

Note: the standard A2 front sight assemblies installed on these 6.8 x 45 UCC barrels have a notch on each side of the rear leg of the sight. This notch is to help easily identify the 6.8 x 45 UCC caliber weapon or Upper Receiver Group from other caliber AR weapons in use on the range or in a rifle rack.


All Kramer Defense products are proudly made in the USA.