Model Variants (Including Prototypes)
M249 - Base Series Designation; based on the Belgian FN Minimi light machine gun.
M249 PIP ("Product Improvement Program") - Improved M249 models with plastic stock, folding carrying handle, barrel handguard, revised bipod, revised flash hider, revised pistol grip and new sighting installations.
M249 PARA - Compact variant intended for paratroopers; shorter barrel and gas cylinder with collapsible butt.
M249 SPW ("Special Purpose Weapon") - US SOCOM variant sans magazine well, vehicle mounting hardware and carrying handle.
Mk 46 Mod 0 - Lightweight US SOCOM variant with Picatinny rail support.
Mk 48 - US SOCOM variant following Mk 46 Mod 0 though chambered for the 7.62x51mm NATO standard cartridge.