A projectile launcher, comprising: an internal tank configured to receive a combustible gas through an inlet, a barrel, a projectile storage portion, a piston, a trigger assembly configured to operate a spool, and a flexible structure configured to wrap around the spool. The flexible structure may be connected to the piston, wherein pulling the trigger assembly causes the spool to rotate to cause the flexible structure to pull the piston forward. The piston may be configured to expand a combustion chamber behind the piston when pulled forward, wherein pulling the trigger assembly causes the combustible gas to enter the combustion chamber created by the piston moving forward. The combustion chamber is configured to collapse after the shot is executed due to a spring bias applied to the piston to a backward position and due to the flexible shaft being released from pulling the piston forward.

A projectile launcher, comprising: an internal tank configured to receive a combustible gas through an inlet, a barrel, a projectile storage portion, a piston, a trigger assembly configured to operate a spool, and a flexible structure configured to wrap around the spool. The flexible structure may be connected to the piston, wherein pulling the trigger assembly causes the spool to rotate to cause the flexible structure to pull the piston forward. The piston may be configured to expand a combustion chamber behind the piston when pulled forward, wherein pulling the trigger assembly causes the combustible gas to enter the combustion chamber created by the piston moving forward. The combustion chamber is configured to collapse after the shot is executed due to a spring bias applied to the piston to a backward position and due to the flexible shaft being released from pulling the piston forward.

A modified projectile includes a projectile, a container, and a liquid propellant in the container. The container is detachably attached to the projectile.

A modified projectile includes a projectile, a container, and a liquid propellant in the container. The container is detachably attached to the projectile.

The present invention relates to a gear cassette (1) for firearms, comprising: a trigger unit (3), the trigger unit comprising means for activating firing of the firearm, and a combustion unit (20) comprising: a combustion chamber part (21) having an inlet end section (22) and an outlet end section (23) and an annular wall (24) arranged between the inlet end section and the outlet end section, the annular wall and the end sections comprising an inner surface (25) and an outer surface (26), at least one gas inlet (31, 32) and a fire outlet (33), and at least one spark plug (34) projecting into the combustion chamber, wherein the combustion unit further comprises a gas hose (6, 7) connected to the gas inlet (31, 32) of the combustion chamber part (21) for bringing the combustion chamber (74) in fluid communication with a gas unit comprising at least one gas container (4, 5), and wherein the trigger unit (3) is adapted to activate firing of the firearm by igniting gas in the combustion chamber.

The present invention relates to a gear cassette (1) for firearms, comprising: a trigger unit (3), the trigger unit comprising means for activating firing of the firearm, and a combustion unit (20) comprising: a combustion chamber part (21) having an inlet end section (22) and an outlet end section (23) and an annular wall (24) arranged between the inlet end section and the outlet end section, the annular wall and the end sections comprising an inner surface (25) and an outer surface (26), at least one gas inlet (31, 32) and a fire outlet (33), and at least one spark plug (34) projecting into the combustion chamber, wherein the combustion unit further comprises a gas hose (6, 7) connected to the gas inlet (31, 32) of the combustion chamber part (21) for bringing the combustion chamber (74) in fluid communication with a gas unit comprising at least one gas container (4, 5), and wherein the trigger unit (3) is adapted to activate firing of the firearm by igniting gas in the combustion chamber.

A projectile launcher, comprising: an internal tank configured to receive a combustible gas through an inlet, a barrel, a projectile storage portion, a piston, a trigger assembly configured to operate a spool, and a flexible structure configured to wrap around the spool. The flexible structure may be connected to the piston, wherein pulling the trigger assembly causes the spool to rotate to cause the flexible structure to pull the piston forward. The piston may be configured to expand a combustion chamber behind the piston when pulled forward, wherein pulling the trigger assembly causes the combustible gas to enter the combustion chamber created by the piston moving forward. Pulling the piston forward loads a projectile into the barrel from the projectile storage portion in response to pulling the trigger. Gas in the combustion chamber is ignited while the piston is pulled forward, and igniting the gas causes a pulse to travel through the piston for executing a shot by launching the projectile through the barrel. The combustion chamber is configured to collapse after the shot is executed due to a spring bias applied to the piston to a backward position and due to the flexible shaft being released from pulling the piston forward. Collapsing the combustion chamber causes hot gas generated from the shot to be released. The gas may be green gas.

A projectile launcher, comprising: an internal tank configured to receive a combustible gas through an inlet, a barrel, a projectile storage portion, a piston, a trigger assembly configured to operate a spool, and a flexible structure configured to wrap around the spool. The flexible structure may be connected to the piston, wherein pulling the trigger assembly causes the spool to rotate to cause the flexible structure to pull the piston forward. The piston may be configured to expand a combustion chamber behind the piston when pulled forward, wherein pulling the trigger assembly causes the combustible gas to enter the combustion chamber created by the piston moving forward. Pulling the piston forward loads a projectile into the barrel from the projectile storage portion in response to pulling the trigger. Gas in the combustion chamber is ignited while the piston is pulled forward, and igniting the gas causes a pulse to travel through the piston for executing a shot by launching the projectile through the barrel. The combustion chamber is configured to collapse after the shot is executed due to a spring bias applied to the piston to a backward position and due to the flexible shaft being released from pulling the piston forward. Collapsing the combustion chamber causes hot gas generated from the shot to be released. The gas may be green gas.

An apparatus includes an energy source and an expansion structure. The energy source is configured to convey an amount of energy operable to increase a pressure of a compressible gas disposed in a chamber. The expansion structure is configured to be placed in fluid communication with the chamber and to receive a flow of the compressible gas in response to the increase in pressure. The expansion structure includes an inlet having a first diameter and an outlet having a second diameter greater than the first diameter and is configured to allow the compressible gas to expand as the compressible gas flows from the inlet to the outlet such that a supersonic free jet of the compressible gas exits the outlet. In some instances, the supersonic free jet of the compressible gas can accelerate, relative to the expansion structure, a projectile disposed outside of the expansion structure.

An apparatus includes an energy source and an expansion structure. The energy source is configured to convey an amount of energy operable to increase a pressure of a compressible gas disposed in a chamber. The expansion structure is configured to be placed in fluid communication with the chamber and to receive a flow of the compressible gas in response to the increase in pressure. The expansion structure includes an inlet having a first diameter and an outlet having a second diameter greater than the first diameter and is configured to allow the compressible gas to expand as the compressible gas flows from the inlet to the outlet such that a supersonic free jet of the compressible gas exits the outlet. In some instances, the supersonic free jet of the compressible gas can accelerate, relative to the expansion structure, a projectile disposed outside of the expansion structure.