POLYMER CARTRIDGE WITH ENHANCED SNAPFIT METAL INSERT AND THICKNESS RATIOS

A high strength polymer-based cartridge, comprising:a polymer case, comprising:a first end having a mouth;a body formed below the mouth and having a propellant chamber and a longitudinal axis;a back end, opposite the first end, and formed below the body, comprising:a first snap ridge comprising a first ridge angle at approximately at 90° to the longitudinal axis;a first snap spacer depending from the first snap ridge and away from the mouth and approximately parallel to the longitudinal axis;a first snap slope depending from the first snap spacer and away from the mouth;a second snap ridge, positioned closer to the first end than the first snap ridge, comprising a second ridge angle at approximately at 90° to the longitudinal axis;a second snap spacer depending from the second snap ridge and away from the mouth and approximately parallel to the longitudinal axis;a second snap slope depending from the second snap spacer and away from the mouth;a leading edge, positioned closer to the first end than the second snap ridge, comprising at least one of a sloped or radiused edge; and an insert configured to engage the back end.