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US3611873A Expired / Lapsed US ⏱️ 0.0 years remaining

Blowback firearm with retarded extraction

Assignee: Individual
•
Filing: 1969-03-21
•
Granted: 1971-10-12
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Expires: 1989-03-21
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Abstract

Abstract In an automatic weapon, blowback pressure extracts the spent, empty shell. In this invention the rate of extraction due to blowback is automatically retarded in proportion to the force of the explosion. This is advantageous for several reasons. For example, if the explosion, and resultant pressure, is abnormally high, the shell is held in place by a semilocked or retarded bolt. The bolt is automatically released as the pressure drops. This action also assures that the maximum amount of energy will be imparted to the projectile, and that the shell will not be prematurely partially ejected with a blowout of the side of the shell.

Inventors

  • 👤 Thormon O Ellison

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 01:53
CPC Classifications
F; F41; F41A; F41A3/00; F41A3/62; F41A3/12; F41A3/54

Claims Analysis

Total Claims: 3
Claim 1
Independent Claim 199 words
Apparatus for automatic guns comprising a barrel, a receiver, a firing chamber for receiving shell-type ammunition, a bolt member supporting the rear end of the shell during firing and having forward extension means extending longitudinally alongside of the shell inside of the receiver to give longitudinal reinforcement to the shell casing during firing, said forward extension means being sufficiently elastic or flexible to permit deflection thereof outwardly into frictional contact with said receiver under pressure accompanying the firing to thereby resist rearward movement of the bolt proportional to the strength of the ammunition and to release the resistance as the pressure subsides to permit the bolt and extension to slide freely, and rearward extension means on said barrel, said rearward extension means having a wedge-shaped surface lying alongside of said forward extension means on said bolt, said forward extension means having a cooperating wedge-shaped surface extending longitudinally thereof and extending in a direction that would be a chord of a circle representing the inner surface of the barrel, said wedgeshaped surfaces being in close proximity whereby outward pressure exerted by the shell during firing causes said wedge-shaped surfaCes to tightly engage each other to thereby increase the frictional resistance.
Claim 2
Dependent Claim 199 words
Apparatus for automatic guns comprising a barrel, a receiver, a firing chamber for receiving shell-type ammunition, a bolt member supporting the rear end of the shell during firing and having forward extension means extending longitudinally alongside of the shell inside of the receiver to give longitudinal reinforcement to the shell casing during firing, said forward extension means being sufficiently elastic or flexible to permit deflection thereof outwardly into frictional contact with said receiver under pressure accompanying the firing to thereby resist rearward movement of the bolt proportional to the strength of the ammunition and to release the resistance as the pressure subsides to permit the bolt and extension to slide freely, and rearward extension means on said barrel, said rearward extension means having a wedge-shaped surface lying alongside of said forward extension means on said bolt, said forward extension means having a cooperating wedge-shaped surface extending longitudinally thereof and extending in a direction that would be a chord of a circle representing the inner surface of the barrel, said wedgeshaped surfaces being in close proximity whereby outward pressure exerted by the shell during firing causes said wedge-shaped surfaCes to tightly engage each other to thereby increase the frictional resistance.
Claim 3
Dependent Claim 56 words
Apparatus as in claim 1 including two of said wedge-shaped surfaces on said rearward extension of said barrel and two cooperating wedge-shaped surfaces on said forward extension of said bolt, the four wedge-shaped surfaces mating in pairs such that outward pressure during shell firing in said firing chamber increases frictional resistance at each of the pairs.

References Cited (Backward Citations)

US1165621A Cited
US2297693A Cited
US2632391A Cited
US3008258A Cited
US3114290A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1974-10-11 1975-04-12 1975-10-12 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1978-10-11 1979-04-12 1979-10-12 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1982-10-11 1983-04-12 1983-10-12 $7700.00 Window Closed / Lapsed

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