The M2 or Browning .50 Caliber Machine, currently manufactured by US Ordnance, is a heavy machine designed towards the end of WW1 by John Browning. It is very similar in design to Browning’s earlier M1919 Browning machine , which was chambered for the .30-06 cartridge. The M2 uses the much larger and much more powerful .50 BMG cartridge, which was developed alongside and takes its name from the itself (BMG standing for Browning Machine). The M2 has been referred to as “Ma Deuce”, as a GI phonetic slang or “the fifty” in reference to its caliber. The design has had many specific designations; the official designation for the current infantry type is Browning Machine, Cal. .50, M2, HB, Flexible. It is effective against infantry, unarmored or lightly armored vehicles and boats, light fortifications and low-flying aircraft. The M2 has had the longest continuous service for a machine in the world.