F41A 21/28
Gas-expansion chambers
Official title: Gas-expansion chambers; Barrels provided with gas-relieving ports (F41A1/06, F41A13/08 {and F41A21/36} take precedence)
F41A21/28 (Gas-expansion chambers) appears on 176 US grants and 135 published applications in this corpus.
Search patents in F41A- Granted patents
- 176
- Published applications
- 135
- Assignees
- 70
- Inventors
- 224
- Latest grant
- 11 Aug 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 2 | 0 |
| 1977 | 2 | 0 |
| 1978 | 2 | 0 |
| 1979 | 1 | 0 |
| 1980 | 0 | 0 |
| 1981 | 0 | 0 |
| 1982 | 0 | 0 |
| 1983 | 1 | 0 |
| 1984 | 1 | 0 |
| 1985 | 4 | 0 |
| 1986 | 1 | 0 |
| 1987 | 0 | 0 |
| 1988 | 1 | 0 |
| 1989 | 2 | 0 |
| 1990 | 2 | 0 |
| 1991 | 1 | 0 |
| 1992 | 3 | 0 |
| 1993 | 4 | 0 |
| 1994 | 3 | 0 |
| 1995 | 3 | 0 |
| 1996 | 1 | 0 |
| 1997 | 0 | 0 |
| 1998 | 6 | 0 |
| 1999 | 2 | 0 |
| 2000 | 3 | 0 |
| 2001 | 1 | 0 |
| 2002 | 3 | 3 |
| 2003 | 3 | 3 |
| 2004 | 3 | 2 |
| 2005 | 0 | 3 |
| 2006 | 2 | 3 |
| 2007 | 0 | 0 |
| 2008 | 2 | 0 |
| 2009 | 0 | 0 |
| 2010 | 2 | 4 |
| 2011 | 2 | 5 |
| 2012 | 4 | 4 |
| 2013 | 4 | 0 |
| 2014 | 5 | 1 |
| 2015 | 2 | 6 |
| 2016 | 8 | 14 |
| 2017 | 9 | 8 |
| 2018 | 13 | 10 |
| 2019 | 12 | 16 |
| 2020 | 13 | 14 |
| 2021 | 13 | 6 |
| 2022 | 3 | 5 |
| 2023 | 6 | 11 |
| 2024 | 7 | 4 |
| 2025 | 9 | 10 |
| 2026 | 5 | 3 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Recent patents
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- Adjustable cant double barrel shotgun suppressor system16 Jun 2026US 12,656,076 B2HuxWrx Safety Co. LLC
- Dynamic ram accelerator system5 May 2026US 12,618,623 B2Pipeline2Space, Inc.
- Blast attenuation device21 Apr 2026US 12,607,428 B2BAE SYSTEMS plc
- Pneumatic launcher barrel housing system6 Jan 2026US 12,516,905 B2
- Firearm barrel having at least one barrel gas port and method of manufacturing the same20 Aug 2026US 2026/0243532 A1WHG Properties, LLC
- Firearm assemblies with multiple gas ports4 Jun 2026US 2026/0153298 A1WHG Properties, LLC
- Firearm Barrel with Non-Metal Outer Sleeve23 Apr 2026US 2026/0110511 A1Blackstone Firearms, LLC
- Ammunition and weapon system18 Dec 2025US 2025/0383173 A1
- Firearm barrel with outer sleeve6 Nov 2025US 2025/0341378 A1Blackstone Firearms, LLC
Most cited
By later US patents
- Improved barrel for paintball gun122US 5,228,427 ASmart Parts, Inc. · 1993
- Recoil reducing mechanism for shotguns65US 4,503,632 A1985
- Firearm sound and flash suppressor having low pressure discharge63US 9,500,427 B12016
- Recoil reducing and piston shock absorbing mechanism56US 4,088,057 ARemington Arms Company, Inc. · 1978
- Lightweight cartridge case and weapon system48US 10,782,107 B1The United States of America as represented by the Secretary of the Army · 2020