Patent ID: 9518794
Filing Date: 2016-12-13
CPC Classification: F41A

Claim Text:
1. An interchangeable choke tube for a shot load of a smoothbore shotgun which causes an initial tightening of progressive form, an expansion, and a final retightening of the shotload, characterized by: an initial tightening of the shotload by a progressive form section, followed by a expansion section having a larger inner diameter than an inner diameter of the progressive form section, which is followed by a final retightening section having a narrower inner diameter than the expansion section, whereby the improvement of the effectiveness of the shotload is provided by the initial tightening of the progressive form section, an ameliorative rearrangement of the shot pellets while passing through the expansion section, resulting in the shot pellets having a smoother entrance into the final retightening section, thereby resulting in the improvement of the distribution of the shot pellets within their pattern during their course of travel after their exit from the barrel.