NAME – T29

NAME (NATIVE) – US Submachine gun T29

COUNTRY OF ORIGIN – USA

DATE OF MANUFACTURE – 1944

CALIBER – 7.62x33mm (.30 M1 Carbine)

OVERALL LENGTH – 53 cm (20 7/8 in) With stock retracted, 74 cm (29 1/8 in) with stock extended, 20.3 cm (8 in) barrel

68.3 cm (26 7/8 in) With stock retracted, 89.2 cm (35 1/8 in) with stock extended, 20.3 cm (14 in) barrel

BARREL LENGTH – 20.8 cm (8.19 in), 35.6 cm (14 in)

RIFLING (TYPE & TWIST) – 1 turn in 50.8 cm (20 in)

BULLET DIAMETER – 7.82 mm (0.308 in)

BULLET WEIGHT – 7.19 g (111 gr)

MUZZLE VELOCITY – 454 m/s (1490 fps) with 20.3 cm (8 in) barrel

463 m/s (1520 fps) with 35.6 cm (14 in) barrel

MUZZLE ENERGY – 742 j (547 ft/lbs) with 20.3 cm (8 in) barrel

772 j (570 ft/lbs) with 35.6 cm (14 in) barrel

WEIGHT (EMPTY) – 3.77 kg (8 lbs 5 oz) with 20.3 cm (8 in) barrel

3.91 kg (8 lbs 10 oz) with 35.6 cm (14 in) barrel

BOLT WEIGHT – 1.02 kg (2 lbs 4 oz)

WEIGHT (LOADED) – 4.27 kg (8 lbs 5 oz) with 20.3 cm (8 in) barrel

4.41 (9 lbs 11.6 oz) with 35.6 cm (14 in) barrel

SIGHTS – Front – Blade, Rear – Fixed peep zeroed at 91 m (100 yds)

EFFECTIVE RANGE – 183 m (200 yds)

OPERATION – Blowback

TYPE OF FIRE – Full automatic

RATE OF FIRE – 90 rpm

CYCLIC ROF – 400 rpm

FEED DEVICE – 30 round box magazine, double column, double feed *

FEED DEVICE WEIGHT (EMPTY) – 0.11 kg (4 oz)

FEED DEVICE WEIGHT (LOADED) – 0.50 kg (1 lb 1.6 oz)

BASIC LOAD – 6 – 30 round magazines (180 rounds)

LOAD WT – 3.0 kg (6 lbs 9.6 oz)

MANUFACTURER – General Motors Corporation, Guide Lamp Division, Dayton, Ohio

STATUS – Obsolete

SERVICE – None, experimental only.

          The basis for the T29 program was to adopt an M3 submachinegun to the M1 Carbine round. This idea was driven by the Germans also using a short rifle cartridge in the MP44 assault rifle series. The T29 was adopted to the M1 Carbine round by a design team led by George Hyde.

There were three specimens of the T29 produced. At two had 35.6 cm (14 inch) barrels while the third had an 20.3 cm (8 inch) barrel. The only real changes to the receiver of the weapon was an increase in the length of the receiver’s magazine well to accommodate the M1 Carbine magazine. The magazine catch was also modified accordingly. The bolt was considerably changed from that of the M3. The front of the bolt was cut back about 9.5 mm (3/8 in) to give the front of the bolt a 15.8 mm (5/8 in) diameter round extension. A steel block about 12.7 mm (.5 in) long was attached to the rear of the bolt for weight. The guide rod locating plate, ahead of the bolt, was also made thicker and given a central hole to match the round extension of the bolt. This system enclosed the bolt head during the last part of its travel forward to fire the cartridge.

     Mainsprings were changed accordingly. A system of two springs were now used in the T29 to drive the bolt and a shorter, stronger spring, to act as a bolt buffer. Changes were also made to the ejector, making it a spring-loaded system. The basic receivers of the weapons were modified M3 versions. The receivers have the M3A1 style of housing assemblies without the cocking handle that was prone to breakage in the M3 submachinegun. Of interest is that the stock used was an M3 stock, without the integral loading tool. The double column, double feed Carbine magazines were easily loaded by hand and did not require a loading tool. The ejection port was lengthened considerably to accommodate the longer M1 Carbine round with the ejection port cover still acting as a safety device.

* Note – Experimental magazines were used for development of the weapon, in addition to standard 15 round M1 Carbine magazines. The production 30 round carbine magazine was not available until April, 1945