Staff Writer (Updated: 12/17/2015):
In 1938, the US Army delivered a request to the Ordnance Department for a lightweight select-fire automatic service rifle chambered for a .30 caliber pistol round to arm various first- and second-line units with a more capable weapon beyond service rifles and pistols. Among these units were machine gun and mortar teams whose cargo was dominated by heavy equipment. These personnel would need a sufficient weapon to which arm themselves with in the event their positions were threatened. While the M1 Garand was an excellent service rifle in its own right, it proved too cumbersome to manage for such overburdened units. The new weapon would also be called to serve rear units such as logistics personnel whose secondary role would be fighting. The initial proposal was not finalized until 1940 to which no fewer than 25 concerns were reached. Winchester was charged with designing the new cartridge. Since the cartridge had yet to be developed, design of the rifle itself was slowed somewhat at the outset.
During this time, a pair of gunsmiths at Winchester were privately developing an automatic weapon for game hunting (in a different caliber) and it was this design that was entered by a Winchester manager (Edwin Pugsley) into the 1941 US Army challenge. The weapon was appropriately redesigned to the requested .30 caliber ammunition while the US Army had since dropped its selective-fire requirement. The weapon stood against 11 other submissions of which only a few made the final cut after May trials. Final trials were held in September of that year with the Winchester design being selected as the winner. In December of 1941, the Empire of Japan attacked the US Navy in Pearl Harbor, Hawaii, officially bringing America into World War 2. The Winchester rifle was assigned the US Army designation of "US Carbine, Caliber 30, M1" - otherwise known as the "M1 Carbine". The cartridge would, therefore, be designated as the "30 M1 Carbine".
As a "carbine" weapon, the M1 Carbine was neither a full-length service rifle nor a submachine gun. Carbines had been generally used throughout military history by mounted troops or specialist soldier types who required a shortened form of a standard-issue "long gun". The M1 certainly fit this mold considering the units that would be issued this weapon in large numbers though, most notably, the M1 did not emerge from any existing long gun then in service - a rather unique aspect to its storied history.
Overall, the M1 was of a very distinct and highly identifiable profile. The body was of a single, solid piece of wood with an integrated grip region, shoulder stock and forend. The major internal working components were inlaid into the wooden body and made for a very robust, yet lightweight, firearm. The trigger unit was positioned in the usual place and made up of the curved trigger assembly and oblong trigger ring. The straight detachable box magazine was inserted into the bottom of the body just ahead of the trigger unit in a conventional fashion. A charging handle was offset to the right side of the receiver. Iron sights were mounted at the receiver rear as well as over the muzzle for some ranged accuracy though the M1 Carbine was never intended for long range work. The barrel protruded a distance away from the body of the gun, covered over partially by another wood portion, and capped with a small muzzle device. Accessories included a shoulder strap looped at the forend and shoulder stock as well as a magazine pouch typically attached at the right side of the stock. The weapon was originally fed via a 15-round detachable box magazine which provided an excellent ammunition supply for a semi-automatic weapon. Overall length was just over 35 inches with an unloaded weight of 5lbs, 7 ounces. The barrel itself measured some 18 inches long and sported 4 grooves in its design with a right-hand twist pattern. Muzzle velocity of the exiting .30 M1 Carbine cartridge was listed at 1,950 feet per second which gave it acceptable "punch". Rate-of-fire was approximately 850-900 rounds per minute.