A compressed gas gun having a bolt and piston movable by the application of compressed gas, and a removable inline cylinder, are provided.

A compressed gas gun having a bolt and piston movable by the application of compressed gas, and a removable inline cylinder, are provided.

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.

A noise reduction device designed for use with air rifles and sub-sonic applications is disclosed. The noise reduction device includes a plurality of collinear rings, each having a plurality of filaments fixed thereto in a radial configuration, so as to define an opening at the center of each of the rings.

A noise reduction device designed for use with air rifles and sub-sonic applications is disclosed. The noise reduction device includes a plurality of collinear rings, each having a plurality of filaments fixed thereto in a radial configuration, so as to define an opening at the center of each of the rings.

A rifled barrel having splines. A projectile has at least one inner fin. A method to spin a projectile to render its shell and its fluid to spin at the approximately the same rate.

A rifled barrel having splines. A projectile has at least one inner fin. A method to spin a projectile to render its shell and its fluid to spin at the approximately the same rate.

A rifled barrel having splines. A projectile has at least one inner fin. A method to spin a projectile to render its shell and its fluid to spin at the approximately the same rate.

A rifled barrel having splines. A projectile has at least one inner fin. A method to spin a projectile to render its shell and its fluid to spin at the approximately the same rate.

A barrel assembly for a paintball gun includes a first barrel portion, a second barrel portion, and an insert. The insert is inserted into and positioned within bores of the first barrel portion and the second barrel portion. The first barrel portion and the second barrel portion include corresponding connection mechanisms that allow the first barrel portion and the second barrel portion to removably couple with one another. The insert includes a ridge that is fixed positioned between the first barrel portion and the second barrel portion when the first barrel portion and the second barrel portion are coupled. The first barrel portion and the second barrel portions can receive inserts with different bore sizes (e.g., inner diameter).