| CPC F41A 3/66 (2013.01) [F41A 11/00 (2013.01); F41A 17/38 (2013.01)] | 11 Claims |

|
1. A rifle comprising:
an upper receiver having a downwardly depending rear lug having a width;
the rear lug defining a transverse lug bore having a selected diameter;
a lower receiver removably attachable to the upper receiver;
the lower receiver defining an upwardly open cavity defined between opposed sidewalls;
the cavity adapted to receive the rear lug when the upper receiver is connected to the lower receiver;
the sidewalls defining lateral sidewall bores having the selected diameter;
the sidewall bores being registered with the transverse lug bore when the upper receiver and lower receiver are in a fully engaged condition;
a pin having an elongated portion received in the transverse lug bore and the sidewall bores;
the pin being movable in a direction along its length between an operating condition and a released condition;
the pin having a first end portion that, when the pin is in the operating condition, is closely received in at least one of the sidewall bores and is closely received within at least a portion of the transverse lug bore such that relative movement of the upper receiver with respect to the lower receiver is prevented;
the first end portion having a lower end portion surface adapted to resist upward movement of the rear lug;
the pin having an intermediate portion adjacent to the lower end portion surface;
the intermediate portion of the pin being thinner than the first end portion;
the intermediate portion having an oblong cross section.
|