The Dead Air Sierra 5 Xeno 5.56 suppressor (Dead Air part no. SIERRA5XM) is a dedicated 5.56 NATO can that ships with a 1/2-28 Xeno flash hider and a Xeno adapter. Dead Air calls it a hard-use silencer, built with welded Cobalt 6 baffles inside a stainless steel outer tube rather than stainless baffles. It is full-auto rated with no barrel length restrictions, and HUB compatible 1.375-24 mounting adapters let it be reconfigured for the shooter’s setup. The Sierra 5 balances overall sound and flash suppression at a compact size and minimal weight, which suits professional use and heavy firing schedules.

Key Specifications

• The caliber rating is 5.56 NATO and .224 Valkyrie, as Dead Air publishes it.
• The energy rating is 2200 ft-lbs, the ceiling Dead Air sets for the Sierra 5.
• Bore diameter is 5.56mm, matched to this dedicated 5.56 design.
• Length is 5.72 inches with the Xeno mount, or 4.87 inches with no adapter.
• Weight is 13.3 ounces with the Xeno mount, or 10.8 ounces with no adapter.
• Diameter is 1.5 inches, a slim profile that sits easily under most handguards.
• Materials are Cobalt 6 baffles and a stainless steel tube, built for heavy firing schedules.
• The finish is black Cerakote over knurled tubing that Dead Air chose for function over form.
• The Xeno package includes a 1/2-28 Xeno flash hider and a Xeno adapter, ready for a standard 5.56 barrel thread.
• Dead Air lists it as full-auto rated with no barrel restrictions, so short barrels are within its limits.

Frequently Asked Questions

What comes with the Sierra 5 Xeno? Dead Air supplies a 1/2-28 Xeno flash hider and a Xeno adapter. Its rear HUB threads are 1.375-24, so other HUB compatible mounting adapters fit.

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.

What is the Sierra 5 rated for? Dead Air rates it for 5.56 NATO and .224 Valkyrie with a 2200 ft-lb energy rating. It is full-auto rated with no barrel restrictions.

Buy the Dead Air Sierra 5 Xeno 5.56 Suppressor

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 Dead Air‘s silencers and suppressed firearms lineup and our Lubbock, Texas team will handle the transfer, and it ships fast to your Class 3 dealer. Dead Air built the Sierra 5 to be the last 5.56 suppressor a shooter needs.