Heckler & Koch MP5 vs SIG MPX

1966–Present

2015–present

~2,000,000 estimated

Unknown

680 mm (26.8 in) stock extended, 550 mm (21.7 in) stock retracted (MP5A3); Varies significantly depending on variant.

425mm (16.7 in) stock folded, 610mm (24 in) extended

115 mm (4.5 in) standard, various lengths depending on variant (e.g., MP5K: 102 mm (4.0 in), MP5SD: 146 mm (5.7 in))

114-203mm (4.5-8 in) — multiple configurations

2.54 kg (5.6 lb) empty (MP5A3)

2.67 kg (5.9 lb) 4.5-inch barrel

15, 30 rounds standard; 10, 20, and 40 round options available

10, 20, or 30 rounds — translucent polymer

Roller-delayed blowback, closed bolt

Gas-operated, short-stroke piston, closed bolt — rifle-derived

Single-stage military trigger; SEF (Safe, Semi-automatic, Full-automatic) or Navy trigger groups available with burst-fire options

Selective fire (safe, semi, full auto on military models)

Rotary drum rear, hooded front post

Flip-up iron sights, full-length MIL-STD-1913 rail