Home / Products / Black Rifle Depot / Cross Machine Tool UPUR-3A Big Bore Billet AR-15 Side Charging Upper Receiver - Slick Side
Cross Machine Tool UPUR-3A Big Bore Billet AR-15 Side Charging Upper Receiver - Slick Side

Cross Machine Tool UPUR-3A Big Bore Billet AR-15 Side Charging Upper Receiver - Slick Side

Lowest Listed Price
$149.95
MSRP
$149.95
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Updated
Aug 26, 2026
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Specifications

MPN
UPUR-3A

Description

Cross Machine Tool UPUR-3A Big Bore Billet AR-15 Side Charging Upper Receiver - Slick SideLooking for something to change up the standard AR-15 formula? This Cross Machine Tool Ultra Precision Upper Receiver is designed for side charging bolt carrier groups and is compatible with Mil-Spec lower receivers. The UPUR-3A is machined from a billet of 7075-T6 aluminum allowing for a custom look and precise dimensions and is much stronger than traditional 6061 aluminum. This Billet AR-15 upper receiver features a slick side design without the forward assist and the enlarged ejection port is compatible with .458 SOCOM, so you can build a precision rifle or a big bore hunting rifle. It is machined with an increased wall thickness for rigidity and the carrier bore diameter is precision cut to ensure consistent and smooth function. The flat top picatinny rail features T-marks to keep track of your optic position if you remove it often and is still compatible with standard charging handles. This CMT Side Charging AR-15 Upper Receiver is compatible with a wide range of parts, so you can build your dream rifle.Features:Machined from billet 7075-T6 aluminumHardcoat anodizedEngraved T-marks and 1913 picatinny railIncreased wall thicknessPrecision cut carrier bore diameter.458 SOCOM sized ejection portNo forward assist, shell deflector, or dust coverCompatible with Bear Creek Arsenal and Young Mfg. side charging BCGsDual charging capabilities with standard charging handleM4 feed rampsCompatible with Mil-Spec lowers and partsCross Machine Tool Co., utilizing the latest machining technologies, offers high quality products that you'll be excited to own. Cross Machine Tool is a veteran owned business that takes pride in manufacturing products you will own. CMT products exceed military standards, so you can build the best AR style rifle possible.
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