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Maxim Defense PDX:SD 300 Blackout Semi-Auto SBR w/ Maxim DSX Suppressor
NFA Item - No Returns

Maxim Defense PDX:SD 300 Blackout Semi-Auto SBR w/ Maxim DSX Suppressor
MAXIM DEFENSE PDX:SD 300 Blackout Semi-Auto SBR w/ Maxim DSX Suppressor
MAXIM DEFENSE PDX:SD 300 Blackout Semi-Auto SBR w/ Maxim DSX Suppressor
MAXIM DEFENSE PDX:SD 300 Blackout Semi-Auto SBR w/ Maxim DSX Suppressor
$3,429.99

In Stock with FREE shipping
No Returns

Class 3 / NFA Items are not eligible for returns. To learn more about purchasing Class 3 / NFA Items, click here.

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Product Description

What's in the Box

  • Maxim PDX:SD 300 Blackout Semi-Auto SBR
  • (1) 20-Round Magazne
  • Cable Lock
  • Owner's Manual

Re-engineering the boundaries of ultra-compact personal defense weapon (PDW) performance, the Maxim Defense PDX:SD .300 BLK Pistol with Maxim DSX Suppressor delivers whisper-quiet, hearing-safe firepower in an agile pistol configuration. Purpose-built from the ground up as a suppressor-tuned system within Maxim’s SDX lineup, the PDX:SD pair an ultra-short 5.5-inch barrel with a custom-engineered DSX suppressor utilizing M-Kore™ technology. Finished in an attractive Arid (Flat Dark Earth) Type III hard coat anodizing, this 300 Blackout pistol generates full-velocity energy while drastically reducing gas blowback, heat buildup, and cyclic wear on internal components.

At the center of its silent lethality, the platform-specific DSX suppressor is constructed from military-grade titanium (6Al-4V), 17-4 stainless steel, and 7075/6061 billet aluminum, carrying no barrel length restrictions under hard firing schedules. Integrated carbon cutters make field maintenance effortless, allowing the suppressor to be fully serviced with common tools. Outfitted with a fast-stabilizing 1:5" twist barrel, a compact Maxim GEN:6 CQB Pistol Brace for maximum stability in a minimal footprint, and a durable DLC/anodized coating, the PDX:SD Pistol collapses down to just 23.75 inches for seamless vehicle transport and close-quarters maneuverability.

Firearm Features

  • Integrated Maxim DSX Suppressor w/ M-Kore™ Technology: Delivers hearing-safe sound reduction on full-power .300 BLK loads in an ultra-compact footprint without compromising velocity or reliability.
  • Military-Grade Materials & Construction: Built for extreme operational durability utilizing 6Al-4V titanium, 17-4 stainless steel, and 7075/6061 aircraft aluminum with no barrel length restrictions.
  • User-Serviceable w/ Integrated Carbon Cutters: Designed for fast, tool-less disassembly using common field tools, featuring internal carbon cutters that eliminate carbon lock and simplify cleaning.
  • 5.5" Fast-Twist 1:5" Barrel: Match-grade 5.5-inch threaded barrel features a fast 1:5" twist rate to stabilize heavy subsonic and lightweight supersonic .300 Blackout projectiles.
  • Maxim GEN:6 CQB Pistol Brace: Ultra-compact, rapid-deploying GEN:6 CQB stabilizing brace provides firm rear support, comfortable cheek positioning, and an exceptionally small storage profile.
  • Reduced Gas Blowback Engine: Purpose-tuned gas dynamics vent propellant gases forward away from the shooter's face while preserving standard cyclic rates for smooth shooting.
  • Arid FDE Type III Hard Coat Anodize & DLC Finish: Coated in a heavy-duty Type III hard coat anodized Arid Flat Dark Earth finish paired with DLC-treated internal components for superior corrosion and friction resistance.
  • Sub-Compact 23.75" Overall Footprint: Collapses down to an ultra-short 23.75-inch overall length, making it ideal for discreet bag carry, truck storage, and dynamic close-quarters applications.

Firearm Specifications

  • Manufacturer: Maxim Defense
  • Model: PDX:SD
  • Caliber: 300 Blackout \
  • Configuration: AR-Pattern Pistol / Integrally Suppressed PDW
  • Caliber: .300 AAC Blackout (300BLK)
  • Barrel Length / Twist Rate: 5.5 inches / 1:5" Twist RH
  • Muzzle Thread Pattern: 5/8"-24 TPI
  • Suppressor Technology: Maxim DSX Suppressor w/ M-Kore™ Technology (User-Serviceable w/ Carbon Cutters)
  • Suppressor Materials: 6Al-4V Titanium, 17-4 Stainless Steel, 7075 & 6061 Aluminum
  • Stabilizing Brace: Maxim GEN:6 CQB Pistol Brace
  • Finish: Type III Hard Coat Anodize & DLC / Arid (Flat Dark Earth - FDE)
  • Overall Length (Collapsed): 23.75 inches
  • Weight: 7.6 lbs

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