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 keeps the noise down without the price of an exotic build. Through-hardened 17-4 stainless baffles, a nitride finish and a full-auto rating give it the durability for long strings of fire between cooldown periods. Two direct thread HUB mounts come in the box, and the HUB-threaded body lets you move to a QD mount whenever you like. It is a straightforward, affordable can for a 5.56 carbine or rifle.

Key Specifications

• The rated cartridges are .22 ARC, 4.6x30mm, 5.56x45mm and 5.7x28mm, which covers the .22-class centerfire rounds.
• Overall length is 6.5 inches with the mount and 6.2 inches without it.
• Weight is 17.4 ounces with the mount and 15.2 ounces without it.
• Body diameter is 1.58 inches, slim enough to fit 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 fine with an ultrasonic cleaner.
• It is full-auto rated, with CMMG noting approximately 240 rounds between cooldown periods.
• Two mounts are included: one 1/2-28 and one 5/8-24 direct thread HUB mount, so common barrel threads are covered out of the box.
• The body is 1.375-24 HUB compatible, so you can pick the QD mount and muzzle device system you prefer.
• A 3/8-inch drive in the welded front end cap works with the 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 cartridges is the ZEROED 556 rated for? CMMG lists .22 ARC, 4.6x30mm, 5.56x45mm and 5.7x28mm for the ZEROED 556.

Which mounts come in the box? CMMG includes two direct thread HUB mounts, one 1/2-28 and one 5/8-24, and the body is 1.375-24 HUB compatible for QD mount systems.

Buy the CMMG ZEROED 556 Direct Thread Suppressor, 6.5-Inch

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.