Firearm having a dual cam, cock on close bolt action and a low creep sear and step trigger assembly

What is this patent about?

’007 is related to the field of bolt action firearms, specifically addressing the mechanical challenges associated with high-velocity rimfire cartridges. Traditional rimfire designs often struggle with the increased main spring tension required to ignite thicker cartridge casings, which typically results in a heavy, difficult bolt lift and increased wear on internal components. The background context involves optimizing the ergonomics of the bolt cycle and improving trigger safety without sacrificing the crispness of the trigger pull.

The underlying idea behind ’007 is to redistribute the mechanical work of the firearm by utilizing a cock-on-close architecture combined with a symmetrical dual-cam interface. By shifting the compression of the heavy main spring from the bolt-opening phase to the bolt-closing phase, the inventor leverages the user's natural forward and downward physical strength. Furthermore, by using two diametrically opposed cam pins and slots, the design eliminates the lateral skewing and friction inherent in single-pin systems, ensuring the bolt remains perfectly centered under high spring loads.

The claims of ’007 focus on a bolt action assembly featuring a main body with a neck portion containing diametrically opposed elongate slots and a cam cylinder with mirrored spiral-shaped slots. The independent claims specifically protect the interaction between a spring retainer and a lateral cam pin that passes through both the neck and the spiral slots to compress the main spring during the closing rotation. Additionally, the claims cover a trigger assembly integrated with a nested stop lever that must be finger-actuated to allow the sear to rotate and release the firing pin.

In practice, when the user rotates the bolt handle downward to lock the action, the spiral cam slots force the dual-headed cam pin and the internal spring retainer forward. This motion compresses the main spring against a plunger held in place by the sear. Because the reactive forces are balanced on both sides of the bolt neck, the assembly avoids the 'binding' effect common in high-tension rimfire rifles, resulting in a smoother, more reliable cycling action even when using heavy-duty springs for cartridges like the .17 WSM.

This invention differentiates itself from prior art by replacing the standard asymmetrical cock-on-opening mechanism with a balanced dual-cam cock-on-close system. While traditional triggers often compromise safety for a light pull, this design incorporates a secondary safety stop lever coaxial with the trigger itself, providing a mechanical block against accidental sear release from drops or jars. This allows for a very short sear engagement—reducing trigger creep—while maintaining a high level of drop-safety through the integrated finger-actuated blocking lever.