|Winchester .224 (E2)
|5.56 mm x 45 mm
The Winchester .224 Experimental
cartridge was Winchester's design
for the 1957 trials before the
adoption of the US M 16 Rifle.
The E2 case was 45 mm long vs the
E1 case at 43mm long, to increase
case capacity to decrease pressures.
It was one of the experiments in the
Mid 1950s and early 1960s by the
USA and NATO to develop a new
Service Rifle Cartridge.
All experiments were scrubbed
after it was decided to adopted the
7.62x51mm, (308 Winchester) as
the new NATO cartridge
As with all experimental cartridges,