{ "apiVersion": 1, "kind": "work-order", "purpose": "Taking the firearm apart for a job such as refinishing, and putting it back together to specification.", "firearm": { "slug": "thompson-m1928", "name": "Thompson Submachine Gun", "manufacturer": { "id": "auto-ordnance", "name": "Auto-Ordnance" }, "category": "submachine-gun", "action": "blowback", "calibers": [ ".45 ACP" ], "alsoKnownAs": [ "M1928A1", "M1A1 Thompson", "Tommy Gun" ], "coversAlso": [ "M1928A1", "M1 and M1A1 Thompson (no Blish lock)", "Semi-automatic Auto-Ordnance Thompson reproductions (with significant differences)" ], "page": "firearms/thompson-m1928.html", "bundle": "api/v1/firearms/thompson-m1928.json", "lastUpdated": "2026-10-29" }, "notices": [ "This work order is written for the Thompson Submachine Gun. It is reported to cover M1928A1; M1 and M1A1 Thompson (no Blish lock); Semi-automatic Auto-Ordnance Thompson reproductions (with significant differences) — if the firearm on the bench is one of those, check the torque notes: values do not always carry over.", "No torque values are recorded for this firearm. Get them from the manufacturer or a gunsmith; do not estimate." ], "disclaimer": { "headline": "Read this before you use anything here.", "points": [ "This is a guide, not an authority. Entries are compiled from manufacturer manuals, technical manuals, published references, and community knowledge. Some of it comes from sources that are not authoritative, and some of it may simply be wrong.", "Always consult the manufacturer's manual for your specific firearm and serial-number range. Manufacturers change designs mid-production without renaming the model. The manual that shipped with your firearm outranks anything on this site.", "Consult a licensed gunsmith for anything beyond routine field stripping and cleaning, for any firearm you are unsure about, and for any procedure marked as gunsmith-recommended here.", "Treat every firearm as loaded. Verify it is unloaded, with the magazine removed and the chamber physically and visually checked, before any procedure in this database. Point it in a safe direction the entire time.", "Disassembly can damage a firearm or injure you. Springs are under tension, parts can launch, and reassembling a firearm incorrectly can make it unsafe to fire in a way that is not obvious from the outside. If a reassembled firearm does not pass a function check, stop and see a gunsmith.", "Torque values are shown in two groups. Values from the manufacturer or the issuing military are shown as such, with the document they came from. Values reported by anyone else — parts makers, gunsmithing publishers, articles, forums — are shown separately with who said them, how reliable that source is, and their exact words. Those are not specifications. Confirm any torque value with the manufacturer or a licensed gunsmith before relying on it.", "Nothing here is legal advice. Firearms law varies by country, state, and city, and some modifications or configurations are regulated or prohibited. You are responsible for knowing and following the law where you are.", "No warranty of any kind. Contributors and maintainers accept no liability for damage, injury, or loss arising from use of this material." ], "page": "disclaimer.html", "legal": { "summary": "Legal notice: this material is third-party information compiled from sources of varying reliability and is provided for general informational and educational purposes only. It is not gunsmithing, technical, safety or legal advice, it is not verified or endorsed by any manufacturer, and it must not be taken as fact. Any work on a firearm beyond the routine field stripping described in its own owner's manual should be performed only by a licensed and insured gunsmith. You use this material entirely at your own risk. Fundamental Build LLC and the project's contributors make no warranty of any kind and accept no liability for death, injury, damage or loss arising from its use. Full terms: LEGAL.md.", "page": "legal.html", "notice": "https://github.com/Fundamental-build-LLC/Pew-Takedown/blob/main/LEGAL.md" } }, "sourcing": { "confidence": "medium", "verification": "armorer-manual-verified" }, "manufacturerDisassembly": { "status": "published", "limit": null, "statement": "The 1929 Auto-Ordnance handbook gives owners full dismounting directions down to the firing mechanism, firing pin and extractor, with only cautions (e.g. remove the magazine catch or breech oiler only if necessary).", "source": { "title": "Handbook of the Thompson Submachine Gun, Model of 1928, Model of 1921; Thompson Semi-Automatic Carbine, Model of 1927 (4th Edition, January 1929)", "publisher": "Auto-Ordnance Corporation, New York", "reliability": "primary", "url": "https://archive.org/download/gunmanual_Thompson_Tommy_Full_Auto_1927/Thompson%20Tommy%20Full%20Auto%201927.pdf", "page": "41", "pdfPage": 22, "pageUrl": "https://archive.org/download/gunmanual_Thompson_Tommy_Full_Auto_1927/Thompson%20Tommy%20Full%20Auto%201927.pdf#page=22", "quote": "The remaining components of the firing mechanism are then free to be removed. The disconnector can be removed from the trigger by simply withdrawing same." } }, "recalls": [], "shopTier": { "tier": 2, "group": "rifle", "rating": "Pew-Takedown editorial rating (1 easy – 3 hardest), not the manufacturer's", "reason": "Only 38 numbered components, but the frame (trigger) group is held by a pivot plate under several springs. The FM says to press trigger and sear down while the plate is withdrawn, and the bolt's hammer, firing pin and spring spring out. The frame has to be withdrawn with a downward pull or it damages the trigger and trip. These are several traps but no timing.", "confidence": "medium", "partCount": { "value": 38, "kind": "line-items", "covers": "Models 1921/1928 component list 1–38 (magazines and sight sub-parts not included)", "basis": "manufacturer-parts-list", "source": { "title": "Handbook of the Thompson Submachine Gun, Model of 1928, Model of 1921; Thompson Semi-Automatic Carbine, Model of 1927 (4th Edition, January 1929)", "publisher": "Auto-Ordnance Corporation, New York", "reliability": "primary", "url": "https://archive.org/download/gunmanual_Thompson_Tommy_Full_Auto_1927/Thompson%20Tommy%20Full%20Auto%201927.pdf", "page": "7", "pdfPage": 5, "pageUrl": "https://archive.org/download/gunmanual_Thompson_Tommy_Full_Auto_1927/Thompson%20Tommy%20Full%20Auto%201927.pdf#page=5", "quote": "38 Trip" } }, "painPoints": [ { "issue": "The sear and trigger pivots are held by a pivot plate under spring pressure. It has to be popped and withdrawn straight while the trigger and sear are pressed down.", "during": "both", "source": { "title": "FM 23-40 Basic Field Manual: Thompson Submachine Gun, Caliber .45, M1928A1 (with Changes 1–4)", "publisher": "War Department", "reliability": "primary", "url": "https://archive.org/download/FM_23_40_B_F_M_T_S_G_C_45_M1928A1_1931/FM%2023-40%20Basic%20Field%20Manual.%20Thompson%20Submachine%20Gun%2C%20Caliber%20.45%2C%20M1928A1%20%281931%29.pdf", "page": null, "pdfPage": null, "pageUrl": null, "quote": "While withdrawing pivot plate with left hand, press down on trigger and sear with thumb of right hand to release pressure of springs on pivots. Do not cant pivot plate during withdrawal." } }, { "issue": "Pushing out the bolt's hammer pin lets the hammer, firing pin and spring spring out and get lost.", "during": "disassembly", "source": { "title": "FM 23-40 Basic Field Manual: Thompson Submachine Gun, Caliber .45, M1928A1 (with Changes 1–4)", "publisher": "War Department", "reliability": "primary", "url": "https://archive.org/download/FM_23_40_B_F_M_T_S_G_C_45_M1928A1_1931/FM%2023-40%20Basic%20Field%20Manual.%20Thompson%20Submachine%20Gun%2C%20Caliber%20.45%2C%20M1928A1%20%281931%29.pdf", "page": null, "pdfPage": null, "pageUrl": null, "quote": "Caution should be exercised to prevent these parts from springing away and becoming lost. The firing pin spring must not be stretched." } }, { "issue": "The lower (frame) group must be pulled down as well as back when it comes off, or the frame latch hits and damages the trigger and trip.", "during": "disassembly", "source": { "title": "FM 23-40 Basic Field Manual: Thompson Submachine Gun, Caliber .45, M1928A1 (with Changes 1–4)", "publisher": "War Department", "reliability": "primary", "url": "https://archive.org/download/FM_23_40_B_F_M_T_S_G_C_45_M1928A1_1931/FM%2023-40%20Basic%20Field%20Manual.%20Thompson%20Submachine%20Gun%2C%20Caliber%20.45%2C%20M1928A1%20%281931%29.pdf", "page": null, "pdfPage": null, "pageUrl": null, "quote": "Failure to pull down as frame is withdrawn causes frame latch to strike against the rear portion ot the trigger and trip, damaging these parts." } }, { "issue": "The long recoil spring can fly loose and kink between actuator and buffer pilot, then bind.", "during": "both", "source": { "title": "TM 9-1215 Ordnance Maintenance: Thompson Submachine Gun, Cal. .45, M1928A1", "publisher": "War Department", "reliability": "primary", "url": "https://archive.org/download/TM9-1215/TM9-1215.pdf", "page": null, "pdfPage": null, "pageUrl": null, "quote": "Care must Ik; taken in removing ami replacing this spring, as it is apt to fly loose ami heroine, twisted lietwcen actuator and pilot," } } ], "minutes": { "strip": 50, "rebuild": 80, "basis": "estimated", "note": "Frame group (pivot plate, sear, trigger, rocker, safety), bolt group (hammer pin, firing pin), actuator, Blish lock, recoil spring/buffer, butt stock, sights.", "source": null }, "stripScope": [ { "assembly": "Receiver", "removes": [ "recoil spring and buffer", "bolt", "actuator and lock (H-piece)", "breech oiler", "rear sight", "ejector" ] }, { "assembly": "Frame group", "removes": [ "rocker and pivot", "safety", "pivot plate", "sear, trigger, disconnector, springs", "magazine catch (only if needed)" ] }, { "assembly": "Bolt", "removes": [ "hammer pin, hammer, firing pin and spring", "extractor (only if needed)" ] }, { "assembly": "Furniture", "removes": [ "butt stock", "grips / forearm" ] } ], "hardware": { "pins": 3, "springs": 7, "detents": 0, "basis": "counted from the manufacturer's parts list (one per key number unless a quantity is given)" }, "specialTools": [ { "tool": "hard-wood block, leather vise jaws and strap wrench", "usedFor": "Barrel removal per TM 9-1215 (not normally needed)" } ], "fitOnRebuild": [ { "check": "Frame latch engaged", "why": "The frame must be locked to the receiver.", "source": null }, { "check": "Function check (safety, trigger reset, feeding, extraction)", "why": "Standard after any detail strip. No single source.", "source": null } ], "assessed": "2026-10-29" }, "videos": [ { "title": "Auto-Ordnance Boot Camp: Tommy Gun Disassembly", "url": "https://www.youtube.com/watch?v=6tCsPMop_Lg", "platform": "youtube", "embedUrl": null, "shows": [ "field-strip" ], "appliesTo": "Auto-Ordnance Tommy Gun (1927-series and M1 semi-auto reproductions; steps 'as described in the manual included with all Auto-Ordnance Thompson firearms')", "published": "2022-09-26", "note": null, "channel": { "id": "UCs_x5EptAOGZ-iyJ9k7VVPw", "name": "Kahr Firearms Group", "url": "https://www.youtube.com/@KahrFirearmsGroup", "owner": "Kahr Firearms Group (parent of Auto-Ordnance / Thompson)" }, "accessed": "2026-10-15" } ], "configurations": [], "tools": [], "phases": [ { "id": "clear", "title": "Clear and make safe", "steps": [ { "n": 1, "instruction": "Point the muzzle in a safe direction and keep your finger off the trigger." }, { "n": 2, "instruction": "Place the selector and safety on safe." }, { "n": 3, "instruction": "Release and remove the magazine or drum.", "tip": "A drum slides out sideways on the M1928; a box magazine releases with a catch.", "partsFreed": [ "Magazine or drum" ] }, { "n": 4, "instruction": "Pull the actuator fully rearward and lock the bolt open." }, { "n": 5, "instruction": "Inspect the chamber and magazine well with a light and physically confirm the chamber is empty.", "warning": "Look and feel." }, { "n": 6, "instruction": "Remove all live ammunition from the work area." } ], "videos": [] }, { "id": "disassemble", "title": "Disassemble", "videos": [ { "title": "Auto-Ordnance Boot Camp: Tommy Gun Disassembly", "url": "https://www.youtube.com/watch?v=6tCsPMop_Lg", "platform": "youtube", "embedUrl": null, "shows": [ "field-strip" ], "appliesTo": "Auto-Ordnance Tommy Gun (1927-series and M1 semi-auto reproductions; steps 'as described in the manual included with all Auto-Ordnance Thompson firearms')", "published": "2022-09-26", "note": null, "channel": { "id": "UCs_x5EptAOGZ-iyJ9k7VVPw", "name": "Kahr Firearms Group", "url": "https://www.youtube.com/@KahrFirearmsGroup", "owner": "Kahr Firearms Group (parent of Auto-Ordnance / Thompson)" }, "accessed": "2026-10-15" } ], "procedures": [ { "procedure": "field-strip", "title": "Field Strip", "level": "field-strip", "configuration": false, "steps": [ { "n": 1, "instruction": "Complete the Clear and Make Safe procedure with the bolt forward and the safety on." }, { "n": 2, "instruction": "Press the frame latch and slide the lower receiver group rearward and off the upper receiver.", "warning": "Hold the trigger pulled and pull the frame down as well as to the rear as you withdraw it. If you do not pull down, the frame latch strikes the rear of the trigger and trip and damages them (FM 23-40 para 6c).", "partsFreed": [ "Lower receiver group" ] }, { "n": 3, "instruction": "Withdraw the actuator, bolt, and recoil spring assembly rearward out of the upper receiver.", "warning": "The recoil spring is under compression.", "partsFreed": [ "Actuator", "Bolt", "Recoil spring assembly" ] }, { "n": 4, "instruction": "On an M1928 pattern, slide the actuator with the lock forward and lift the lock (the Blish H-piece) out of the actuator.", "warning": "M1 and M1A1 bolts have no H-piece. Do not go looking for one.", "partsFreed": [ "Blish lock H-piece" ] }, { "n": 5, "instruction": "Clean the bore, chamber, bolt face, and receiver interior." } ] }, { "procedure": "breech-oiler-removal", "title": "Remove the breech oiler", "level": "detail-strip", "configuration": false, "steps": [ { "n": 1, "instruction": "Field strip the gun so that the frame, recoil spring, bolt, lock and actuator are out of the receiver." }, { "n": 2, "instruction": "Hold the receiver upside down in your left hand, muzzle to the front." }, { "n": 3, "instruction": "Hook the end of your right forefinger under the front end of the right side of the breech oiler and pull up and to the left until the right side of the oiler is out of its groove in the receiver." }, { "n": 4, "instruction": "Hold the oiler in this position with your right thumb." }, { "n": 5, "instruction": "Without moving the thumb, hook your right forefinger under the front end of the left side of the oiler and pull the oiler out of the groove in the left side of the receiver." }, { "n": 6, "instruction": "With your right forefinger, pull the entire front end of the oiler up and to the rear." }, { "n": 7, "instruction": "Lift the oiler out of the receiver, front end first.", "partsFreed": [ "Breech oiler" ] } ] }, { "procedure": "magazine-disassembly", "title": "Disassemble the 20-round box and 50-round drum magazines", "level": "detail-strip", "configuration": false, "steps": [ { "n": 1, "instruction": "Box magazine: slide out the floor plate while holding your fingers over the bottom of the magazine tube.", "warning": "Hold fingers over bottom of magazine tube to keep magazine spring from flying out.", "partsFreed": [ "Floor plate" ] }, { "n": 2, "instruction": "Box magazine: remove the magazine spring and the follower.", "partsFreed": [ "Magazine spring", "Follower" ] }, { "n": 3, "instruction": "Drum magazine: remove the winding key.", "partsFreed": [ "Winding key assembly" ] }, { "n": 4, "instruction": "Drum magazine: lift off the cover.", "partsFreed": [ "Cover assembly" ] }, { "n": 5, "instruction": "Drum magazine: lift up on the end of the rotor retainer and slide it out of its engagement in the hub.", "partsFreed": [ "Rotor retainer" ] }, { "n": 6, "instruction": "Drum magazine: remove the rotor assembly from the body.", "warning": "Further disassembly of magazine is not necessary and is prohibited (FM para 7a). TM 9-1215 para 12 adds that the rotor and spring case are riveted together.", "partsFreed": [ "Rotor assembly" ] } ] }, { "procedure": "bolt-group-detail-strip", "title": "Disassemble the bolt group", "level": "detail-strip", "configuration": false, "steps": [ { "n": 1, "instruction": "Field strip the gun and take the bolt out of the receiver." }, { "n": 2, "instruction": "Push the hammer pin out of the bolt from the left side.", "warning": "The hammer, firing pin and firing pin spring will tend to spring out under the impulse of the firing pin spring. Keep them from springing away and becoming lost. The firing pin spring must not be stretched.", "partsFreed": [ "Hammer pin", "Hammer", "Firing pin", "Firing pin spring" ] }, { "n": 3, "instruction": "Only if the extractor must come out, insert a corner of the actuator flange under the head of the extractor on the face of the bolt and pull the extractor out and up to withdraw it from its groove.", "warning": "Do not remove the extractor for ordinary cleaning — it is apt to break or take a set. Do not lift it higher than necessary for its lug to clear the anchorage hole.", "partsFreed": [ "Extractor" ] } ] }, { "procedure": "receiver-group-detail-strip", "title": "Remove the rear sight leaf, ejector and fore grip", "level": "detail-strip", "configuration": false, "steps": [ { "n": 1, "instruction": "Field strip the gun so that the bolt is out of the receiver." }, { "n": 2, "instruction": "Drive out the sight base pin and remove the rear sight leaf.", "warning": "Take care that the rear sight leaf plunger and spring do not fly out.", "partsFreed": [ "Sight base pin", "Rear sight leaf", "Rear sight leaf plunger", "Sight plunger spring" ] }, { "n": 3, "instruction": "Lift the leaf just enough to disengage the detent, and unscrew the ejector from the receiver.", "warning": "Do not try to unscrew the ejector with the bolt assembled and in the forward position. To do so may damage the ejector and bolt.", "partsFreed": [ "Ejector" ] }, { "n": 4, "instruction": "Unscrew the fore grip screw and remove the fore grip.", "partsFreed": [ "Fore grip screw", "Fore grip" ] } ] }, { "procedure": "butt-stock-detail-strip", "title": "Disassemble the butt stock", "level": "detail-strip", "configuration": false, "steps": [ { "n": 1, "instruction": "Remove the butt stock from the gun." }, { "n": 2, "instruction": "Remove the screws and lift out the butt stock slide assembly.", "partsFreed": [ "Butt stock slide assembly", "Screws" ] }, { "n": 3, "instruction": "Drive out the butt stock catch pin and remove the catch and its spring.", "partsFreed": [ "Butt stock catch pin", "Butt stock catch", "Butt stock catch spring" ] }, { "n": 4, "instruction": "Only to remove the catch button, file its pin to round and drive it out.", "partsFreed": [ "Catch button" ] }, { "n": 5, "instruction": "Remove the butt stock plate.", "partsFreed": [ "Butt plate" ] }, { "n": 6, "instruction": "If necessary, remove the trap spring and drive out the trap pin.", "tip": "The bracket is riveted to the butt plate; leave it.", "partsFreed": [ "Trap spring", "Trap pin" ] }, { "n": 7, "instruction": "Remove the sling swivel screws and lift out the swivel plate.", "partsFreed": [ "Sling swivel screws", "Swivel plate" ] }, { "n": 8, "instruction": "If necessary, spring the swivel from the plate.", "partsFreed": [ "Sling swivel" ] } ] }, { "procedure": "barrel-removal", "title": "Remove the barrel, compensator and front sight", "level": "detail-strip", "configuration": false, "steps": [ { "n": 1, "instruction": "Disassemble the gun so that only the receiver and barrel remain." }, { "n": 2, "instruction": "Wedge a block of hard wood in the receiver to prevent springing of the sides." }, { "n": 3, "instruction": "Clamp the receiver in a vise with leather jaws." }, { "n": 4, "instruction": "Unscrew the barrel from the receiver with a strap wrench.", "tip": "A pipe wrench may be used only if the barrel is to be scrapped.", "partsFreed": [ "Barrel" ] }, { "n": 5, "instruction": "To move the front sight and compensator to a new barrel, drive out the front sight pin.", "tip": "TM para 10c(1): do not remove compensator or sight unless necessary.", "partsFreed": [ "Front sight pin" ] }, { "n": 6, "instruction": "Drive the front sight rearward off the barrel.", "partsFreed": [ "Front sight" ] }, { "n": 7, "instruction": "Unscrew the compensator with a strap wrench.", "partsFreed": [ "Cutts compensator" ] } ] } ] }, { "id": "refinish", "title": "Refinish", "components": [ { "name": "Lower receiver group", "procedure": "field-strip", "level": "field-strip", "step": 2 }, { "name": "Actuator", "procedure": "field-strip", "level": "field-strip", "step": 3 }, { "name": "Bolt", "procedure": "field-strip", "level": "field-strip", "step": 3 }, { "name": "Recoil spring assembly", "procedure": "field-strip", "level": "field-strip", "step": 3 }, { "name": "Blish lock H-piece", "procedure": "field-strip", "level": "field-strip", "step": 4 }, { "name": "Breech oiler", "procedure": "breech-oiler-removal", "level": "detail-strip", "step": 7 }, { "name": "Floor plate", "procedure": "magazine-disassembly", "level": "detail-strip", "step": 1 }, { "name": "Magazine spring", "procedure": "magazine-disassembly", "level": "detail-strip", "step": 2 }, { "name": "Follower", "procedure": "magazine-disassembly", "level": "detail-strip", "step": 2 }, { "name": "Winding key assembly", "procedure": "magazine-disassembly", "level": "detail-strip", "step": 3 }, { "name": "Cover assembly", "procedure": "magazine-disassembly", "level": "detail-strip", "step": 4 }, { "name": "Rotor retainer", "procedure": "magazine-disassembly", "level": "detail-strip", "step": 5 }, { "name": "Rotor assembly", "procedure": "magazine-disassembly", "level": "detail-strip", "step": 6 }, { "name": "Hammer pin", "procedure": "bolt-group-detail-strip", "level": "detail-strip", "step": 2 }, { "name": "Hammer", "procedure": "bolt-group-detail-strip", "level": "detail-strip", "step": 2 }, { "name": "Firing pin", "procedure": "bolt-group-detail-strip", "level": "detail-strip", "step": 2 }, { "name": "Firing pin spring", "procedure": "bolt-group-detail-strip", "level": "detail-strip", "step": 2 }, { "name": "Extractor", "procedure": "bolt-group-detail-strip", "level": "detail-strip", "step": 3 }, { "name": "Sight base pin", "procedure": "receiver-group-detail-strip", "level": "detail-strip", "step": 2 }, { "name": "Rear sight leaf", "procedure": "receiver-group-detail-strip", "level": "detail-strip", "step": 2 }, { "name": "Rear sight leaf plunger", "procedure": "receiver-group-detail-strip", "level": "detail-strip", "step": 2 }, { "name": "Sight plunger spring", "procedure": "receiver-group-detail-strip", "level": "detail-strip", "step": 2 }, { "name": "Ejector", "procedure": "receiver-group-detail-strip", "level": "detail-strip", "step": 3 }, { "name": "Fore grip screw", "procedure": "receiver-group-detail-strip", "level": "detail-strip", "step": 4 }, { "name": "Fore grip", "procedure": "receiver-group-detail-strip", "level": "detail-strip", "step": 4 }, { "name": "Butt stock slide assembly", "procedure": "butt-stock-detail-strip", "level": "detail-strip", "step": 2 }, { "name": "Screws", "procedure": "butt-stock-detail-strip", "level": "detail-strip", "step": 2 }, { "name": "Butt stock catch pin", "procedure": "butt-stock-detail-strip", "level": "detail-strip", "step": 3 }, { "name": "Butt stock catch", "procedure": "butt-stock-detail-strip", "level": "detail-strip", "step": 3 }, { "name": "Butt stock catch spring", "procedure": "butt-stock-detail-strip", "level": "detail-strip", "step": 3 }, { "name": "Catch button", "procedure": "butt-stock-detail-strip", "level": "detail-strip", "step": 4 }, { "name": "Butt plate", "procedure": "butt-stock-detail-strip", "level": "detail-strip", "step": 5 }, { "name": "Trap spring", "procedure": "butt-stock-detail-strip", "level": "detail-strip", "step": 6 }, { "name": "Trap pin", "procedure": "butt-stock-detail-strip", "level": "detail-strip", "step": 6 }, { "name": "Sling swivel screws", "procedure": "butt-stock-detail-strip", "level": "detail-strip", "step": 7 }, { "name": "Swivel plate", "procedure": "butt-stock-detail-strip", "level": "detail-strip", "step": 7 }, { "name": "Sling swivel", "procedure": "butt-stock-detail-strip", "level": "detail-strip", "step": 8 }, { "name": "Barrel", "procedure": "barrel-removal", "level": "detail-strip", "step": 4 }, { "name": "Front sight pin", "procedure": "barrel-removal", "level": "detail-strip", "step": 5 }, { "name": "Front sight", "procedure": "barrel-removal", "level": "detail-strip", "step": 6 }, { "name": "Cutts compensator", "procedure": "barrel-removal", "level": "detail-strip", "step": 7 } ], "manufacturerPartsList": { "parts": 38, "scope": "Part I \"List of Components of Thompson Submachine Gun Calibre .45\" (numbered 1-38, keyed to Plates II-III) covering Models 1921 and 1928. Unnumbered magazine (XX, L, C) and sight component lists on pp. 8-9 not transcribed." }, "partsDiagrams": [], "materials": [ { "component": "Receiver", "material": "steel", "finish": "blued", "appliesTo": "Thompson 1927A-1, T1 models", "note": "Auto-Ordnance's current semi-automatic reproduction, not an original submachine gun.", "source": { "title": "Thompson 1927A-1 — Overview and Specs (Auto-Ordnance)", "publisher": "Auto-Ordnance (Kahr Firearms Group)", "reliability": "primary", "url": "https://www.auto-ordnance.com/thompson-1927a-1/", "page": null, "pdfPage": null, "pageUrl": null, "quote": "The Tommy Gun is available with a blued steel receiver (T1 models) or a lighter weight aluminum receiver (T5 models)." } }, { "component": "Receiver", "material": "aluminum", "finish": null, "appliesTo": "Thompson 1927A-1, T5 models", "note": "Auto-Ordnance's current semi-automatic reproduction, not an original submachine gun.", "source": { "title": "Thompson 1927A-1 — Overview and Specs (Auto-Ordnance)", "publisher": "Auto-Ordnance (Kahr Firearms Group)", "reliability": "primary", "url": "https://www.auto-ordnance.com/thompson-1927a-1/", "page": null, "pdfPage": null, "pageUrl": null, "quote": "The Tommy Gun is available with a blued steel receiver (T1 models) or a lighter weight aluminum receiver (T5 models)." } }, { "component": "Stock", "material": "American Walnut", "finish": "polished", "appliesTo": "Thompson 1927A-1 (T1)", "note": "Auto-Ordnance's current semi-automatic reproduction, not an original submachine gun.", "source": { "title": "Thompson 1927A-1 — Overview and Specs (Auto-Ordnance)", "publisher": "Auto-Ordnance (Kahr Firearms Group)", "reliability": "primary", "url": "https://www.auto-ordnance.com/thompson-1927a-1/", "page": null, "pdfPage": null, "pageUrl": null, "quote": "The fixed stock is crafted in luxurious polished American Walnut and has a vertical foregrip." } }, { "component": "Whole firearm", "material": "steel", "finish": "parkerized", "appliesTo": "Thompson T1-C Commando", "note": "The maker states this for the firearm as a whole, not for a named part. Auto-Ordnance's current semi-automatic reproduction, not an original submachine gun.", "source": { "title": "Thompson 1927A-1 — Overview and Specs (Auto-Ordnance)", "publisher": "Auto-Ordnance (Kahr Firearms Group)", "reliability": "primary", "url": "https://www.auto-ordnance.com/thompson-1927a-1/", "page": null, "pdfPage": null, "pageUrl": null, "quote": "The Thompson T1-C “Commando” model features parkerized steel and all wood stock, rear grip and horizontal foregrip in a durable black finish." } }, { "component": "Frame and receiver", "material": "solid steel or aluminum", "finish": "blued steel or black anodized aluminum", "appliesTo": "Thompson M1 (TM1 steel / TM1C aluminum alloy) — semi-auto M1A1-style", "note": "Auto-Ordnance's current semi-automatic reproduction, not an original submachine gun.", "source": { "title": "Auto-Ordnance (Kahr Firearms Group) — ", "publisher": "Auto-Ordnance (Kahr Firearms Group)", "reliability": "primary", "url": "https://www.auto-ordnance.com/thompson-m1/", "page": null, "pdfPage": null, "pageUrl": null, "quote": "The frame and receiver are milled from solid steel or aluminum, the wood is genuine American walnut, and the overall finish is a blued steel or black anodized aluminum." } } ], "note": "The components the procedures above separate. Coating, masking and cure are outside this database; follow your coating system's instructions. A part the manufacturer marks \"factory fit\" should not be swapped or reworked." }, { "id": "reassemble", "title": "Reassemble", "videos": [], "procedures": [ { "procedure": "barrel-removal", "title": "Remove the barrel, compensator and front sight", "configuration": false, "steps": null, "instruction": "Reverse the steps of \"Remove the barrel, compensator and front sight\"." }, { "procedure": "butt-stock-detail-strip", "title": "Disassemble the butt stock", "configuration": false, "steps": null, "instruction": "Reverse the steps of \"Disassemble the butt stock\"." }, { "procedure": "receiver-group-detail-strip", "title": "Remove the rear sight leaf, ejector and fore grip", "configuration": false, "steps": null, "instruction": "Reverse the steps of \"Remove the rear sight leaf, ejector and fore grip\"." }, { "procedure": "bolt-group-detail-strip", "title": "Disassemble the bolt group", "configuration": false, "steps": null, "instruction": "Reverse the steps of \"Disassemble the bolt group\"." }, { "procedure": "magazine-disassembly", "title": "Disassemble the 20-round box and 50-round drum magazines", "configuration": false, "steps": null, "instruction": "Reverse the steps of \"Disassemble the 20-round box and 50-round drum magazines\"." }, { "procedure": "breech-oiler-removal", "title": "Remove the breech oiler", "configuration": false, "steps": null, "instruction": "Reverse the steps of \"Remove the breech oiler\"." }, { "procedure": "magazine-reassembly", "title": "Reassemble the box and drum magazines", "configuration": false, "steps": [ { "n": 1, "instruction": "Drum magazine: place the rotor assembly in the body." }, { "n": 2, "instruction": "Drum magazine: slide the rotor retainer back into its engagement in the hub." }, { "n": 3, "instruction": "Drum magazine: replace the cover." }, { "n": 4, "instruction": "Drum magazine: replace the winding key." }, { "n": 5, "instruction": "Box magazine: insert the follower and magazine spring into the tube." }, { "n": 6, "instruction": "Box magazine: compress the spring with your fingers and slide the floor plate back on.", "warning": "Keep the spring covered with your fingers so it cannot fly out." } ], "instruction": null }, { "procedure": "bolt-group-reassembly", "title": "Reassemble the bolt group", "configuration": false, "steps": [ { "n": 1, "instruction": "If the extractor was removed, slide it into place, lifting its head only enough to clear the stud.", "warning": "Avoid excessive pressure on the extractor." }, { "n": 2, "instruction": "Insert the firing pin and firing pin spring in the bolt.", "warning": "Do not stretch the firing pin spring." }, { "n": 3, "instruction": "Place the hammer in position with its rounded edge upward." }, { "n": 4, "instruction": "Push the hammer pin into place." } ], "instruction": null }, { "procedure": "receiver-group-reassembly", "title": "Reinstall the fore grip, ejector, rear sight leaf and breech oiler", "configuration": false, "steps": [ { "n": 1, "instruction": "Install the fore grip and screw in the fore grip screw." }, { "n": 2, "instruction": "With the bolt out of the receiver, screw the ejector all the way home." }, { "n": 3, "instruction": "Place the rear sight leaf plunger and spring, position the rear sight leaf and drive in the sight base pin.", "warning": "Keep the plunger and spring from flying out." }, { "n": 4, "instruction": "Reinstall the breech oiler, rear end first, by reversing the removal steps so that both sides seat in their grooves in the receiver." }, { "n": 5, "instruction": "Replace the actuator, lock, bolt, recoil spring and frame as in the entry's reassembly procedure." } ], "instruction": null }, { "procedure": "reassembly", "title": "Reassembly", "configuration": false, "steps": [ { "n": 1, "instruction": "On an M1928 pattern, place the lock in the actuator guideways with the word \"UP\" readable from the rear and the arrow pointing toward the muzzle." }, { "n": 2, "instruction": "Insert the bolt, actuator, and recoil spring assembly into the upper receiver and seat them." }, { "n": 3, "instruction": "Slide the lower receiver group onto the upper until the frame latch engages.", "warning": "Confirm the latch is engaged before handling the weapon further." }, { "n": 4, "instruction": "Cycle the action several times and perform the function check." } ], "instruction": null } ] }, { "id": "torque", "title": "Torque", "coverage": "none-recorded", "manufacturer": [], "reported": [], "notes": "The official military manuals give no torque value. They say: \"If the rear grip is loose, inspect screw threads in frame and on screw for wear, and the screw for straightness.\" (TM 9-1215 Ordnance Maintenance: Thompson Submachine Gun cal .45, M1928A1 (1942), PDF p. 6 (frame))" }, { "id": "function-check", "title": "Function check", "checks": [ "Verify the firearm is unloaded with no magazine inserted before each step.", "Cycle the action by hand and confirm the bolt returns fully into battery.", "With the safety on, press the trigger. The hammer or striker must not release.", "Move the safety to fire, cycle the action, and press the trigger. It should release.", "Hold the trigger back, cycle the action, and release slowly to feel the disconnector reset.", "Confirm the magazine seats and locks positively and releases cleanly.", "Confirm the upper and lower receiver groups are latched together securely.", "Confirm the actuator moves freely through its full travel." ], "videos": [] } ], "troubleshooting": [], "sources": [ { "n": 1, "id": null, "title": "FM 23-40: Thompson Submachine Gun, Caliber .45, M1928A1", "publisher": "U.S. War Department", "reliability": "primary", "url": null, "accessed": null }, { "n": 2, "id": null, "title": "TM 9-1215: Thompson Submachine Guns, Caliber .45, M1 and M1A1", "publisher": "U.S. Department of the Army", "reliability": "primary", "url": null, "accessed": null }, { "n": 3, "id": "war-department-us-army-1942-8abba0", "title": "TM 9-1215 Ordnance Maintenance: Thompson Submachine Gun cal .45, M1928A1 (1942)", "publisher": "War Department (US Army), 1942", "reliability": "primary", "url": "https://archive.org/details/TM9-1215", "accessed": "2026-09-27" }, { "n": 4, "id": "thompson-m1928-parts-manual", "title": "Handbook of the Thompson Submachine Gun, Model of 1928, Model of 1921; Thompson Semi-Automatic Carbine, Model of 1927 (4th Edition, January 1929)", "publisher": "Auto-Ordnance Corporation, New York", "reliability": "primary", "url": "https://archive.org/download/gunmanual_Thompson_Tommy_Full_Auto_1927/Thompson%20Tommy%20Full%20Auto%201927.pdf", "accessed": "2026-09-27" }, { "n": 5, "id": "auto-ordnance-specs-9bd29c", "title": "Thompson 1927A-1 — Overview and Specs (Auto-Ordnance)", "publisher": "Auto-Ordnance (Kahr Firearms Group)", "reliability": "primary", "url": "https://www.auto-ordnance.com/thompson-1927a-1/", "accessed": "2026-10-03" }, { "n": 6, "id": "auto-ordnance-doc-0a144b", "title": "Auto-Ordnance (Kahr Firearms Group) — ", "publisher": "Auto-Ordnance (Kahr Firearms Group)", "reliability": "primary", "url": "https://www.auto-ordnance.com/thompson-m1/", "accessed": "2026-10-03" }, { "n": 7, "id": "fm-23-40", "title": "FM 23-40 Basic Field Manual: Thompson Submachine Gun, Caliber .45, M1928A1 (with Changes 1–4)", "publisher": "War Department", "reliability": "primary", "url": "https://archive.org/download/FM_23_40_B_F_M_T_S_G_C_45_M1928A1_1931/FM%2023-40%20Basic%20Field%20Manual.%20Thompson%20Submachine%20Gun%2C%20Caliber%20.45%2C%20M1928A1%20%281931%29.pdf", "accessed": "2026-10-03" }, { "n": 8, "id": "tm-9-1215", "title": "TM 9-1215 Ordnance Maintenance: Thompson Submachine Gun, Cal. .45, M1928A1", "publisher": "War Department", "reliability": "primary", "url": "https://archive.org/download/TM9-1215/TM9-1215.pdf", "accessed": "2026-10-03" } ] }