FN Herstal MK1 Self Loading Semi Auto Shotgun

Posted: 04/01/2026

FN Herstal MK1 Self Loading Semi Auto Shotgun

The FN SLP MK I (Self-Loading Police) is a 12-gauge, gas-operated semi-automatic shotgun designed for tactical and competitive use, featuring an 8+1 round capacity (2.75″), a 22-inch hard-chromed barrel, and an Active Valve System. Known for fast cycling and reduced recoil, it has a 43-inch overall length, matte black synthetic stock, and adjustable sights. Includes carrying case.

Specifications:

  • Gauge: 12-gauge (3″ chamber).
  • Operation: Active Valve Gas System (fast-cycling).
  • Capacity: 8+1 rounds (2.75″ shells); 7+1 rounds (3″ magnum shells).
  • Barrel Length: 22″ (hard-chromed bore).
  • Overall Length: 43″.
  • Weight: ~8 lb.
  • Stock: Matte black synthetic with checkered gripping panels.
  • Sights: Low-profile adjustable folding rear blade and red fiber-optic front.
  • Rail: Top-mounted Weaver-pattern rail.