Thompson 1928 Navy, 1921 overstamp
Official wording
Thompson, Model 1928, Navy, 1921 overstamp, cal. .45ACP, submachinegun, mfd. by Colt.
What this entry requires
- ATF REQUIRESMade or imported as stated: “mfd. by Colt”
- INFOATF states no date; production was about 1921–1928.
- INFOStill an NFA firearm; only registered examples transfer, with ATF approval (26 U.S.C. 5812, 5861).
Editorial facts · Our research
- Country
United StatesBasis: no citation - Manufacturer
- Colt’s Patent Firearms Mfg. Co.Basis: the ATF wording
- Type
- SMGBasis: the ATF wording
- Action
- Select-fire / autoBasis: the ATF wording
- Caliber
- .45 ACPBasis: the ATF wording
- Made
- 1921–1928production; ATF states no dateBasis: estimate ¹
- Service
- Military
Source
- Official wording
- ATF P 5300.11, April 2025 edition · Section IV · PDF p. 88 ↗ · ATF original ↗
- Entries
- 1 line
- Verbatim check
- Checked against the PDF text before every release
- Editorial facts
- Confidence: Medium · Last revised 18 October 2026 (Evidence pass) · How we rate confidence
- References
- 1. Wikipedia, “Thompson submachine gun” ↗, years (estimate: partly supports it): Colt made the initial 15,000 Thompsons (first production as the Model of 1921); in 1927 the U.S. Navy ordered 500 guns with a lower rate of fire, designated the Model of 1928; overstamp year not dated
- Fact tags
- ATF the ATF wording states it.
- REF ¹ an outside reference supports it; the number points to the list of references.
- ESTIMATE an approximate or indirect reading, for example the production range of the base model.
- NO CITATION we haven’t attached a reference for this fact; it’s our editorial reading, not ATF’s.
- Source checked
- 20 October 2026: ATF’s page still lists the April 2025 edition
- Corrections
- None
Historical context
Image: Wikimedia Commons, “Thompson submachine gun noBG.png” by National Park Service, CC BY-SA 3.0. Retrieved October 2026.
Summary: Wikipedia, “Thompson submachine gun”. Text CC BY-SA 4.0.
FROM WIKIPEDIA
The Thompson submachine gun is a blowback-operated, selective-fire submachine gun invented and developed by Brigadier General John T. Thompson, a United States Army officer, in 1918. It was designed to break the stalemate of trench warfare of World War I, although early models did not arrive in time for actual combat. The Thompson saw early use by the United States Marine Corps during the Banana Wars, the United States Postal Inspection Service, the Irish Republican Army, and the Republic of China; the FBI, previously an unarmed agency, adopted their use following the 1933 Kansas City massacre.