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US 6,931,978 B1Granted
Rebound attenuation device for automatic firearms
AssigneeSNC Technologies Inc.
InventorSylvain Dionne
Life of this patent
Estimating the term…
Abstract
A blow-back operating automatic firearm has a sliding mass carried with its bolt carrier assembly to increase the dwell time of the bolt at the breech when the bolt is in battery position for firing. The sliding mass reduces the tendency of the bolt to bounce-off the head end of the seated cartridge, thereby reducing the risk that a misfiring will occur.
Claims12
An automatic firearm operating on the basis of a blow-back action, said firearm having:
- 1) a barrel with a breech and a chamber for receiving a round to be fired,
- 2) a receiver into which the barrel is mounted, and
- 3) a unitary bolt carrier assembly including a bolt, a firing pin and a carrier fixed for movement as a unit, said firing pin being axially aligned with said chamber, said assembly being slidingly mounted in said receiver for shifting during cycling of the weapon between a first position wherein the bolt is in-battery against said breech and a second position wherein said bolt carrier assembly is fully removed from the breech while cycling in a full blowback mode;
- 4) a return spring, seated within the weapon for urging the bolt carrier assembly towards the in-battery position when the weapon is cycling;
- and
- 5) weight means slideably mounted within a containment space that travels with the bolt carrier assembly for sliding motion with respect to said bolt carrier assembly,
- whereby, when the weapon is cycling with the bolt carrier assembly having moved rearwardly away from its first position against said breech, to said second position, said weight means will slide away from the breech in its containment space and so remain on the return stroke of the cycle until the bolt is again at the in-battery position, and when the bolt carrier assembly has returned to the in-battery position, the weight means will slide forwardly in its containment space towards the breech to the forward limit of its travel, bearing against the bolt carrier assembly when it comes to the in-battery position and thereby increasing the dwell-time for the bolt when it is in the in-battery position during automatic firing, allowing time to ensure that the firing pin will effectively advance to fire a round.
4 more elements
A conversion kit for an automatic firearm, said automatic firearm having in its standard form:
- a) a standard barrel and a standard chamber of respective given diameters that are dimensioned to fire standard ammunition, said standard ammunition comprising a cartridge with a projectile and a cartridge case which are of a diameter that is substantially equal to the diameter of the said chamber;
- b) a standard receiver into which the barrel is mounted;
- c) a bolt carrier assembly comprising a bolt carrier, and a bolt with a standard firing pin and bolt recess with a face through which the firing pin will operate by advancement into said recess upon firing,
- said training kit for operation of the firearm on the basis of a blow-back action comprising:
- a training bolt carrier assembly comprising:
- (i) a unitary training bolt carrier assembly including a bolt, a firing pin and a carrier fixed for movement as a unit, said firing pin being mounted so as to be axially aligned with said chamber, said training bolt carrier assembly being slidingly mounted in said receiver for shifting during cycling of the weapon between a first position wherein the bolt is in-battery against said breech and a second position wherein said training bolt carrier assembly is fully removed from the breech while cycling in a full blowback mode;
- and
- (ii) weight means slideably mounted within a containment space that travels with the bolt carrier assembly for sliding motion with respect to said training bolt carrier assembly
- whereby, when the weapon is cycling with the training bolt carrier assembly having moved rearwardly away from its first position against said breech, to said second position, said weight means will slide away from the breech in its containment space and so remain on the return stroke of the cycle until the bolt is again at the in-battery position, and when the training bolt carrier assembly has returned to the in-battery position, the weight means will slide forwardly in its containment space towards the breech to the forward limit of its travel, bearing against the training bolt carrier assembly when it comes to the in-battery position and thereby increasing the dwell-time for the bolt when it is in the in-battery position during automatic firing, allowing time to ensure that the firing pin will effectively advance to fire a round.
6 more elements
Dependencies are inferred from the claim text.