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Cross Machine Tool UPUR-4 Billet AR-15 Upper Receiver - Slick Side

CMT · Upper Receiver

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Cross Machine Tool UPUR-4 Billet AR-15 Upper Receiver - Slick Side

Best price

$140.00at Dirty Bird

checked Nov 13, 2026

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Specifications

Manufacturer
CMT
Platform
AR-15

Where to buy

StorePriceAvailabilityBuyAdd to build
Dirty Bird Best price $140.00checked Nov 13, 2026 Check store Buy at Dirty Bird
AR15Discounts 5% off $178.00checked Nov 13, 2026 Check store Buy at AR15Discounts

Prices and availability change often, so confirm on the store's site before you buy. We may earn a commission from these links.

Price history

Dashed line = out of stock. Tracking since Oct 28, 2026.

Show the prices as a table
StoreLatestLowestHighest
AR15Discounts$178.00$178.00$178.00
Dirty Bird$140.00$140.00$140.00

Since Oct 28, 2026.

About this part

The Cross Machine Tool UPUR-4 Billet AR-15 Upper Receiver - Slick Side is an AR-15 upper receiver from CMT. It's sold by 2 stores, from $140.00 to $178.00.

From the manufacturer

Looking for something to change up the standard AR-15 formula? This Cross Machine Tool Ultra Precision Upper Receiver is designed for AR-15 rifles is compatible with Mil-Spec lower receivers. The UPUR-4 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 is machined for use with Mil-Spec dust covers. 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 compatible with standard charging handles. This CMT Slick Side 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 aluminum Hardcoat anodized Engraved T-marks and 1913 picatinny rail Increased wall thickness Precision cut carrier bore diameter No forward assist or shell deflector M4 feed ramps Compatible with Mil-Spec lowers and parts Cross 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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$140.00 at Dirty Bird
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