M16 vs SIG SG 552 Commando

1964–Present

1998–present

8,000,000+ units (including all variants and licensed production)

Unknown

990 mm (39 in) with stock extended; 860 mm (33.9 in) with stock collapsed (carbine)

730 mm (stock extended)

508 mm (20 in) standard; 406 mm (16 in) for carbine variants

226 mm

3.26 kg (7.2 lb) empty, standard rifle; 3.40 kg (7.5 lb) carbine

3.10 kg

30 rounds standard STANAG; 20, 40, 60 round options and drum magazines available

30 rounds

Direct‑impingement gas system with rotating bolt, short‑stroke operation

Gas-operated, rotating bolt

Single‑stage military trigger; three‑round burst mechanism on A2/A4 models

Selective fire

Standard: detachable carrying handle with integrated rear aperture (M16A1) or flat‑top receiver with Picatinny rail and removable iron sights (A4); front post fixed

Diopter rear, post front