AR-45 .45 ACP 16" Slick Side LRBHO M-LOK Upper Assembly, BCG and Charging Handle

AR-45 16" Upper: Specs

This AR-45 16" upper assembly by Moriarti Armaments is built on a slick side billet upper receiver and features the Last Round Bolt Hold Open (LRBHO) function for enhanced operation with Glock-style lower receivers. Chambered in .45 ACP and built with premium materials, this upper delivers reliable performance, durability, and compatibility with AR-45 platforms.

Features

Barrel:

• 16 inch match-grade barrel chambered in .45 ACP

• 4150 CrMoV steel, black nitride finish

• 1:16 twist rate

• Threaded 5/8x24 with A2 flash hider

• Integrated feed ramp

Upper Receiver:

• Slick side billet upper made from certified 7075-T6 aluminum

• Type III Class 2 hardcoat anodized

• Includes LRBHO feature for Glock magazine compatibility

• Compatible with all AR-15, AR-9, and AR-45 mil-spec components

Gas System:

• Blowback operation for reliable pistol-caliber cycling

Handguard:

• Rifle-length M-LOK free-float rail

• Slim and lightweight profile

• Aircraft-grade aluminum, hardcoat anodized

Bolt Carrier Group:

• AR-45 ramped BCG

• 8620 steel, phosphate finish

• Precision milled for Glock-style and Colt-style AR-45 lowers

Charging Handle:

• Standard mil-spec AR-15 charging handle included

Upper comes fully assembled and test-fired. Manufactured in the USA by Moriarti Armaments. Images may not be the exact representation of the item.

FAQ

What lower does it fit?

A dedicated pistol-caliber AR lower that takes Glock-style .45 ACP magazines. A standard AR-15 lower with 5.56 magazines will not feed it.

How does it operate?

It is a direct blowback pistol-caliber design with no gas tube or gas block, so a heavy PCC buffer is used for reliable cycling.

Does it have last round bolt hold open?

Yes. It has LRBHO, so the bolt locks back after the last round when used with an LRBHO-compatible lower.

Is a lower receiver included?

No. This is an upper assembly only; the lower receiver and magazine are sold separately.

Related: AR-45 upper assemblies · pistol caliber carbines