Wilson Arms/Heckler & Koch "MP5SD" Submachine Gun, Class III/NFA Fully Transferable Machine Gun, with Extra Magazines

A highly desirable MP5 SD-style collectible, this 1986 West German-manufactured HK began life as a semi-automatic carbine and was later reconfigured in the United States into a selective-fire, closed-bolt submachine gun patterned after the famed “Schalldaempfer” integrally suppressed MP5 SD.

• Manufactured in West Germany in 1986
• Originally produced as a semi-automatic carbine
• Reconfigured in the United States as a selective-fire, closed-bolt submachine gun
• Built in emulation of the legendary MP5 SD “Schalldaempfer” integrally silenced variant
• Strong collector appeal due to its association with elite units, including U.S. Navy SEAL operators
• MP5 SD-style design significance:
  • The original SD system used a ported barrel to bleed off gas pressure
  • This reduced standard 9mm NATO ball ammunition to subsonic velocity
  • The suppressor system was designed to manage both bled-off gas and muzzle blast
  • Allowed effective sound reduction without requiring special subsonic ammunition
  • Maintained significant parts commonality and training overlap with standard MP5 models
• This example uses a more modern detachable silencer; additional silencer details are noted in the Item B description
• Retains the SD-style barrel porting
• A visible ring of ports can be seen approximately halfway up the bore
• Sights:
  • Hooded post front sight
  • Four-position drum rear sight
• Furniture and exterior features:
  • Ribbed heat-shield forearm
  • Textured ambidextrous pistol grip
  • Fixed buttstock
• Receiver markings:
  • “MP5 SD HK” prominently marked on top of the receiver
  • Wilson Arms address visible on the left side beneath the stock
• Receiver configuration:
  • “Pin” configuration
  • Restored paddle magazine release functionality
• Internal components:
  • Factory original full-automatic-compatible bolt carrier
  • Bolt carrier marked “P5/87” on the rear
  • Bolt head marked “IJ422”
• Trigger group:
  • “Hinge pin” style ambidextrous trigger pack
  • Selector positions include full automatic, semi-automatic, and safe
  • Matching pictographic selector markings on the housing
• Included accessories:
  • Three extra magazines

A standout piece for advanced HK and MP5 collectors, this firearm combines West German manufacture, SD-style historical appeal, selective-fire configuration, recognizable markings, and desirable MP5 features in one highly collectible package.

B) S&H Arms SD Silencer, Class III/NFA Silencer
Steel and alloy construction, 12 inches in overall length, with an expansion chamber in the rear to accept the gases vented by the barrel porting and a baffle stack in the front half.