Skip to Content

U.S. Arms M4 UTAW Champion 300 Blackout AR Pistol

ATF regulated items have restrictions and requirements:

  • Your order will ship only to a Federal Firearms License holder.
  • We are not currently shipping to CA, CT, DC, HI, MD, MA, MN, NJ, NY, or VA.
  • Please be sure to contact your local FFL dealer prior to placing your order to ensure they are still accepting transfers. Some FFL dealers are not open due to Covid-19.
  • Customer must read, understand, and agree to customer terms and conditions.



The U.S. Arms Company M4 UTAW Champion Series is the most advanced weapon system we offer. We took the key design elements from our M4 UTAW Champion Rifle and fit it in a package that automatically creates smiles. This weapon system has it all. It is lightweight, accurate, and durable. We stand behind our name on every rifle and weapon system we manufacture. The Champion Series is the main platform used to showcase our bleeding edge technology and what we are capable of at U.S. Arms Company. This weapon system is offered in .223 Wylde or .300 Blackout chambering.

The M4 UTAW Champion Series AR Pistol can be configured with several Cerakote options for the handguard, trigger guard, upper receiver, and lower receiver. This AR Pistol comes specced with our patented “Cam Lock” lower receiver so that you get the tightest receiver fit on the market, making for the best 300 blackout pistol available. The Cam Lock lower receiver will also fit any mil-spec upper assembly. We are proud to be “Home of the World’s Tightest Receivers”. Every detail was considered in the development, right down to the 300 blackout magazine fitment, which is designed to lock securely to the lower receiver.

This Blackout pistol is available in multiple colors and finishes:

  • Cerakote Black
  • Cerakote Chocolate Brown
  • Cerakote Woodland Camo
  • Cerakote Arctic Camo

The barrel installed in this weapon system is derived from a cold hammer forged 416R stainless match grade blank. At 8″ in length, this shorter barrel is great for a compact feel and small enough so it’s always secured in the right place of your home or vehicle. The barrel is turned, glass bead blasted, and equipped with a nickel boron barrel extension. As a result of using a nickel boron extension and a U.S. Arms nickel boron bolt carrier group, the shooter experiences extremely smooth cycling. To aid in the best shooting experience, the M4 UTAW Champion AR Pistol also comes standard with a state of the art gas system consisting of an SLR .750” adjustable titanium gas block along with an SLR pistol length Melonite gas tube. This allows the shooter to adjust gas flow according to the type of ammunition and suppressor combination being used. This pistol is suppressor ready straight out of the box or violin case. We are proud to run Elftmann Tactical triggers in this weapon systems. Our M4 UTAW Pro Series Rifle comes equipped with a trigger second to none in its class; the Elftmann Match Trigger, which is easily adjustable from 4lbs to 2 3/4lbs without removing the trigger from the lower parts. As a result of this performance, it only made sense to have this trigger in our M4 UTAW Champion AR Pistol. This gives the shooter a custom, crisp and clean trigger break every time the weapon system is fired. Other additions to this series are Magpul MBUS Pro steel iron sights, a Maxim Defense CQB Gen 6 Pistol Brace with an H1 buffer assembly, an ambidextrous Radian Raptor charging handle, and a Strike Industries Venom flash hider. This weapon system is then packaged in a discreet violin AR pistol case from Peak Cases.

The U.S. Arms M4 UTAW Champion Series is meant to set you apart from the crowd in looks and performance, whether it is a Champion Rifle or Champion 300 Blackout AR Pistol with a shorter barrel. The M4 UTAW Champion Series is the highest level of excellence from U.S. Arms Company. We took everything good about our M4 UTAW Champion Rifle put it in an AR pistol package that can fit under the seat of a car, next to a nightstand, or in the closest camouflaged in a violin case. This weapon system provides a signature look and design aesthetic that’s unlike any other in the market, while giving the shooter highest level of confidence and flawless performance in competitions, sport shooting, and home defense for years to come.


Note: Cerakote items may require up to 2 weeks processing time.

Note: 30 round magazines will NOT be included in shipments to Oregon, Rhode Island, Vermont, or any other jurisdiction where such magazines are prohibited.



.300 AAC Blackout

Barrel Length


Barrel Profile


Muzzle Thread

1 / 2 × 28 threads per inch

Gas System


Mounting System



5.82 lbs


23" – 25.6"


One 30-round Lancer L5-AWM Black

Lower Receiver

U.S. Arms Cam-Lock

Product Benefits

  • Designed and engineered to allow significant weight reduction without sacrificing strength
  • Shoots MOA or less with match grade ammunition when equipped with Cam-Lock lower receiver
  • Machined to aerospace tolerances in an ISO certified aerospace facility

Details and Build Materials

  • Receiver Set: 7075-T6 aluminum mated set with optional Cam-Lock technology by U.S. Arms
  • Trigger: Elftmann Tactical drop-in Match Trigger 2.75lbs to 4lbs adj.
  • Safety: TrigerTech Ambidextrous AR Safety 45-90 (See Gen II M4 UTAW Champion for photos)
  • Hand Grip: ERGO Grips Flat Top Tactical SUREGRIP
  • Pistol Brace: Maxim CQB Pistol: Gen 6 – PDW Brace
  • Bolt Carrier Group: U.S. Arms Nickel boron M16/4 full-auto, MP tested, with properly staked gas key
  • Charge Handle: Radian Raptor Ambidextrous
  • Handguard: 7.375″ aluminum free-floating with full-length or continuous top Picatinny rail, side and top M-LOK handguard slots, and side QD mount points
  • Sights: MAGPUL MBUS Pro front and rear
  • 8-Inch Barrel: Cold Hammer Forged 416R stainless match blank, 6 groove, 1:7 twist, glass bead blasted, and a nickel boron extension
  • Chamber: 300 Blackout
  • Gas System: SLR low profile titanium .750″ adjustable gas block and SLR pistol length Melonite gas tube
  • Muzzle Device: Strike Industries Venom flash hider / flash suppressor to minimize muzzle blast
  • Magazine: 1 Lancer Systems L5AWM 30 round 300 blackout magazine
  • Case: Peak Multi Gun Violin Case