The CMMG Banshee Mk4 FourSix pistol in 4.6x30mm with an Armor Black Cerakote finish (brand part no. 46A3E0DAB) was the first AR-pattern firearm ever released to the U.S. civilian market in this caliber, a lightweight, flat-shooting cartridge originally paired with the Heckler & Koch MP7. CMMG builds the FourSix on a direct-impingement operating system with an 8-inch 4140 chromoly barrel cut at a fast 1-in-5.9 twist, and a CMMG ZEROED linear compensator caps the 1/2×28-threaded muzzle. The billet 6061-T6 aluminum upper pairs with a forged 7075-T6 Mk4 lower, and the CMMG EML7 M-LOK handguard runs M-LOK slots on both sides, the bottom, and between the top Picatinny rail sections. Among AR pistols chambered for a niche, high-velocity round, this FourSix configuration favors shooters who want 5.7x28mm-like ballistics at a lower ammunition cost.

Key Specifications

• Chambered in 4.6x30mm, this pistol runs a 40-round CMMG magazine.
• The barrel measures 8 inches, made from 4140 chromoly, salt bath nitride treated.
• Rifling twist is a fast 1-in-5.9 inches, matched to the small-diameter 4.6x30mm bullet.
• The operating system is direct impingement.
• A CMMG ZEROED linear compensator caps the 1/2×28-threaded muzzle.
• The upper receiver is billet 6061-T6 aluminum; the lower is forged 7075-T6 aluminum.
• The CMMG EML7 M-LOK handguard carries slots on both sides, the bottom, and between the top rail sections.
• The finish is Armor Black Cerakote.
• Unloaded weight is 3.9 pounds, with an overall length of 23.7 inches.

Frequently Asked Questions

What is 4.6x30mm? A lightweight, high-velocity round originally developed for the H&K MP7, ballistically similar to 5.7x28mm but less expensive to shoot.

What is the magazine capacity? 40 rounds, using CMMG’s proprietary FourSix magazine.

What operating system does this pistol use? Direct impingement, cycling through an 8-inch chromoly barrel.

Buy the CMMG Banshee Mk4 FourSix Pistol

A first-to-market 4.6x30mm chambering and a billet upper make this FourSix a genuinely distinct AR pistol. Order it from our Lubbock, Texas gun shop for fast, insured shipping to your FFL.