Winchester Lightweight Military Rifle

Around 1957-58 Winchester submitted a lightweight scaled-up M1 carbine design called the Winchester Lightweight Military Rifle. It was lightweight at 5.5 lbs loaded and with a twenty inch barrel. Winchester had developed a cartridge called the .224E1 with ball powder firing a 53 gr bullet at 3300 fps. Due to chamber pressure problems they redesigned the cartridge as the 224E2 which proved satisfactory also with a 53 gr bullet at 3300 fps. Remington also developed a 22 caliber cartridge during this period (223 Rem).

The two cartridges could both be fired in the AR-15 but the Remington could not be fired in the Winchester. After 1958 the development of the Winchester was discontinued.

left 224E@ Winchester and 222 Remington Special

IIRC, that one and many others are in the Cody Museum. All the good stuff is out west apparently.