The CMMG ZEROED 556 suppressor is CMMG’s standard-length can for 5.56mm and other centerfire .22 caliber firearms (CMMG part no. 11DB032). At 6.5 inches it is the standard-length option for keeping the report down, and the through-hardened 17-4 stainless baffles carry a nitride finish and a full-auto rating. Two direct thread HUB mounts, a 1/2-28 and a 5/8-24, come in the box. The 1.375-24 HUB thread on the body lets you move to a QD mount whenever you like. It is a durable, affordable can for a 5.56 carbine or rifle.

Key Specifications

• Bore diameter is .224 caliber, sized for 5.56x45mm and other .22-class centerfire rounds.
• Overall length is 6.5 inches with the mount, or 6.2 inches without it.
• Weight is 17.4 ounces with the mount and 15.2 ounces without.
• Body diameter is 1.58 inches, so it fits under most rifle handguards.
• Construction is heat-treated 17-4 stainless steel with a tubeless, laser-welded baffle design.
• The finish is nitride, a surface-hardening treatment that resists corrosion and is safe in an ultrasonic cleaner.
• The can is full-auto rated, with CMMG’s note of approximately 240 rounds between cooldown periods.
• Two mounts come in the box: one 1/2-28 and one 5/8-24 direct thread HUB mount, covering the two most common barrel threads.
• The body is 1.375-24 HUB compatible, so a QD mount and muzzle device system can be added later.
• A 3/8-inch square drive in the welded front cap works with 7/8-inch wrench flats on the mounts, so common tools handle mount changes.

Frequently Asked Questions

Do I need ATF approval to buy this? No. As of October 9, 2026, ATF no longer requires Form 4 approval, registration or a tax stamp for suppressors. It transfers on a Form 4473 with a background check through a Class 3 (SOT) dealer. State and local laws still apply.

Which calibers and barrel lengths is it rated for? CMMG lists .22 ARC, 4.6x30mm, 5.56x45mm and 5.7x28mm, with minimum barrel lengths of 5 inches for 5.7x28mm and 10.5 inches for 5.56mm.

Is there a shorter version? Yes. CMMG also makes the ZEROED 556K, which measures 5.5 inches with the mount for hosts where length matters more.

Buy the CMMG ZEROED 556 Suppressor, 5.56x45mm, Direct Thread, Nitride

As of October 9, 2026, this suppressor transfers on a Form 4473 with a background check at your Class 3 (SOT) dealer, with no Form 4 or tax stamp; state and local laws still apply. Order through CMMG‘s silencers and suppressed firearms lineup and our Lubbock, Texas team will handle the transfer, and it ships fast to your Class 3 dealer. The standard 556 is the full-length choice when suppression volume matters more than length.