FMK-3 vs Thompson Submachine Gun

1974–1993

1921–Present

Unknown

~1,500,000 units (World War II peak production) and limited post‑war runs

605 mm (stock folded) / 805 mm (stock extended)

762 mm (30.0 in) with stock extended; 660 mm (26.0 in) with stock folded (M1A1)

200 mm

254 mm (10.0 in) standard; 305 mm (12.0 in) for some export models

3.05 kg

4.4 kg (9.7 lb) empty (M1); 3.9 kg (8.6 lb) empty (M1A1)

40 rounds

20‑round box, 30‑round box, 50‑round drum, 100‑round drum (rare)

Blowback, telescoping bolt

Simple blow‑back, open‑bolt, selective‑fire; rate of fire 600–1,250 rpm depending on model

Single-stage

Two‑stage trigger: semi‑automatic (first pull) and fully‑automatic (second pull) on early models; later models use a single‑stage full‑auto trigger with a selector switch

Fixed front post and flip-up rear aperture

Rotary drum rear sight with 50, 100, 200, 300 yard settings; hooded front post; optional adjustable rear sight on later police variants