Maxim Defense PDX 300 Blackout Complete Upper - Arid - 5.5"

Manufactured by Maxim Defense
SKU: MXM-47826
MPN: MXM-47826
Manufactured by Maxim Defense
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NOTE: This upper assembly has a barrel less than 16” in length. These uppers are intended for use in AR-15 pistols or legal short-barreled rifles. Other configurations may violate Federal law.

The Maxim Defense PDX Complete Upper Receiver is chambered in 300 Blackout and is compatible with standard AR style lower receivers. The PDX 300 BLK features a 5.5” barrel while still being a traditional AR style gas system and retaining all the reliability. The Maxim Hatebrake muzzle brake directs gas and concussion down range away from the shooter and decreases the flash signature making it more bearable for the user when used in close quarters. If you are looking to change up your collection, check out the Maxim Defense .300 Blackout PDX AR-15 Complete Upper.

  • 5.5” barrel chambered in .300 BLK
  • Maxim Hatebrake muzzle brake
  • Flat dark earth anodized
  • M-LOK free float handguard with hand stop
  • Billet machined receiver
  • Ambidextrous charging handle
  • Standard BCG
  • Compatible with Mil-Spec lowers

The upper receiver is machined from billet aluminum and hardcoat anodized brown and tan and the free float handguard features M-LOK attachment slots and QD sling swivel slots as well as a hand stop. This complete upper receiver includes a bolt carrier group and ambidextrous charging handle.
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Barrel Length5.5
BrandMaxim Defense
Caliber Gauge300 Blackout
Gas System LengthPistol
Gas System TypeDirect Impingement
Muzzle DeviceMaxim Defense Hatebrake

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