https://peertube.dngr.us/videos/watch/623ad5b5-9e5b-4760-a2f1-160d55b1dc19 See our Thompson manual at: http://www.amazon.com/Submachine-Guns-Caliber-45-M3A1/dp/1940453119 Join us on Patreon. Visit https://www.patreon.com/PeriscopeFilm This WWII U.S. Army film from 1942 describes the operation of the Thompson Submachine Gun. The Thompson submachine gun (nicknamed the Thompson) is an American submachine gun, invented by John T. Thompson in 1918, that became infamous during the Prohibition era. It was a common sight in the media of the time, being used by both law enforcement officers and criminals. The Thompson was also known informally as: the "Tommy Gun", "Trench Broom", "Trench Sweeper", "Chicago Typewriter", "Chicago Piano", "Chicago Style", "Chicago Organ Grinder", and "The Chopper". As the film shows, the firing cycle is divided into three phases: the backward movement of recoiling parts, the forward movement of recoiling parts, and the trigger mechanism. 00:00 start At 0:35 - 1:09, the explanation of the firing cycle is introduced, which is divided into three phases. In the first phase, after firing, pressure is transmitted from the bolt to the lock and receiver. The high chamber pressure ensures that the lock remains engaged with the receiver, keeping the bolt in place until the pressure subsides. Between 1:09 - 1:52, it is explained that the lock is made of bronze, while the bolt and receiver are steel. As the chamber pressure decreases, the lock moves upward, disengaging from the receiver and allowing the bolt to move backward. From 1:52 - 2:38, the lock's angle ensures that the bolt moves back only when pressure is low enough. The backward movement ejects the spent cartridge and compresses the recoil spring, storing energy for the forward movement. From 2:38 - 3:37, as the bolt moves back, it releases the hammer, which moves the firing pin rearward. The spent cartridge remains on the bolt face due to the extractor. After moving back about 2 inches, the ejector pushes the empty case out through the ejector opening. The bolt’s rearward motion is slowed by the buffer pad. At 3:37 - 4:08, the bolt has two sear notches: if it recoils fully, the front notch engages, and if it recoils partially, the rear notch engages. At 4:08 - 5:24, the second phase, the forward movement of recoiling parts, begins. The bolt moves forward under recoil spring tension, pushing a new cartridge into the chamber. The extractor snaps onto the cartridge rim, and just before locking, the lock cams down into the locking grooves. The hammer then strikes the receiver, pivots, and fires the cartridge by hitting the firing pin. Between 5:24 - 6:29, the bolt stops when it strikes the receiver abutment. The hammer’s motion ensures that the firing pin moves forward into the cartridge. The third phase, the trigger mechanism, is described between 6:29 - 7:02. Pulling the trigger rotates the trigger pivot, moving the disconnector and sear lever, which releases the sear notch and allows the bolt to move forward. From 7:02 - 7:55, the difference between semi-automatic and full-automatic fire is explained. In semi-auto mode, the rocker pivot is set at "single." As the bolt moves forward, it disengages the disconnector, resetting the sear for the next shot. In full-auto mode, the rocker pivot is lowered, preventing the bolt from engaging the rocker, keeping the sear disengaged for continuous fire while the trigger is held. At 8:10 - 8:51, the safety mechanism is described. In the firing position, the safety pivot allows the sear to move. In the safe position, the safety locks the sear in its upper position. The safety can only be engaged when the bolt is to the rear. From 8:51 - 9:40, the magazine mechanism is covered. The magazine catch holds the magazine in place. The box magazine is held by a stud on the catch, while the drum magazine is held by a rectangular catch. Finally, from 9:40 - 10:51, the bolt-hold-open feature for box magazines is explained. This feature functions only with the box magazine. A fin on the magazine follower rises as rounds are depleted. The fin moves the trip, disengaging the disconnector and engaging the sear, which holds the bolt open when the last round is fired. The film ends at 10:51 with background music. Motion picture films don't last forever; many have already been lost or destroyed. We collect, scan and preserve 35mm, 16mm and 8mm movies -- including home movies, industrial films, and other non-fiction. If you have films you'd like to have scanned or donate to Periscope Film, we'd love to hear from you. Contact us via the link below. This film is part of the Periscope Film LLC archive, one of the largest historic military, transportation, and aviation stock footage collections in the USA. Entirely film backed, this material is available for licensing in 24p HD and 2k. For more information visit http://www.PeriscopeFilm.com Source: https://www.youtube.com/watch?v=KGOljZBIu_0 Mirrored from Periscope Film (https://www.youtube.com/@PeriscopeFilm) Fri, 12 Jun 2026 03:26:03 GMT https://validator.w3.org/feed/docs/rss2.html PeerTube - https://peertube.dngr.us https://peertube.dngr.us/lazy-static/avatars/41a6fee9-7f57-42d0-a5fc-5db4f1af2e31.png https://peertube.dngr.us/videos/watch/623ad5b5-9e5b-4760-a2f1-160d55b1dc19 All rights reserved, unless otherwise specified in the terms specified at https://peertube.dngr.us/about and potential licenses granted by each content's rightholder.