T29 .30 Caliber Grease Gun Serial Number X38
The T29 M3A1 submachine gun, converted to fire the M1 carbine .30 caliber cartridge. The 30-round magazine was fabricated from two 15-round carbine magazines.
The experimental T29 submachine gun was developed by the Guide Lamp Division of General Motors during the fall of 1944. The T29 is a straight blowback M3A1 “Grease Gun” chambered for the .30 carbine cartridge. The barrel is 14 inches in length; the overall length is 28.8 inches. Development was terminated with the introduction of the select-fire M2 carbine.
Savage Submachine Gun .45ACP Serial Number X-1
Savage .45 caliber submachine gun designed by Eugene Reising has features from Mr. Reising’s Model 50 submachine gun.
The experimental Savage submachine gun, caliber .45, was manufactured by Savage Arms, Utica, New York. Equipped with a folding spike bayonet, magazine and sling, this submachine gun shares many features with the production Reising M50 submachine gun and feeds from a 20-round Reising magazine. The weapon was designed in the 1940s by Eugene Reising for Savage Arms.
High Standard Submachine Gun .45 ACP Serial Number 7
High Standard .45 caliber submachine gun serial number 7, made for the Ordnance Department’s submachine gun trials. The production 9mm version was designated as the UD42 and manufactured for the United Defense Supply Corporation by the Marlin Arms Company.
The High-Standard Submachine Gun Caliber .45 was designed by Carl G. Swebilius of High Standard with the patents assigned to the corporation. The .45 caliber prototypes were made by High Standard; production UD42 9mm models were manufactured by Marlin for the United Defense Supply Corporation. Reportedly only seven weapons in caliber .45 ACP were made for submission to various testing boards.
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