Following the announcement by the U.S. military that they were looking for a new 'light rifle' to replace the 1911 pistol being used by support troops, Springfield armory would submit a rifle designed by John C. Garand, the creator of the M1 Garand rifle.
Garand's first submission was a gas operated rifle with an unusual lay-out. It has a top feeding magazine that was positioned at a 45 degree angle. Because of this, the iron sights were offset, and the charging handle was positioned on the top. This first submission was judged in testing to be excellent in almost every way, except for the placement of the magazine, in which people were split on weather it should be underneath or above. Springfield's second submission in the September 15th test was re-designed substantially, as the magazine was re-positioned on the bottom, and the select fire option (required in the May 8th test) was removed. While the basic action had not been changed, the testing concluded that Garand's second model was insufficient and required more development time.
The Garand light rifle(s), as were all light rifle submissions, were chambered for the '.30 caliber "light rifle" cartridge designed by Winchester. This would be adopted as the .30 Carbine cartridge.
First variant: the top feeding model submitted to the May 8th trials.
Second variant: the bottom feeding model submitted to the September 15th trials.
'Model D': A separate variation with modified iron sights.
War Baby! The U.S. Caliber .30 Carbine, Vol. 1