Recoil shock absorber for long barrel firearms
Embodiments of the present invention provide significant firearm recoil force reduction and can be integrated within a traditional firearm stock. Such recoil shock absorbers include a body assembly, plunger assembly, and return spring. The body assembly includes a shock tube, cylinder end, and accumulator. The shock tube includes an opening at its distal end, the cylinder end is rotatably coupled to the shock tube, and the accumulator is coupled to the cylinder end. The cylinder end can be selectably/adjustably aligned with the shock tube opening, resulting in a selectable/adjustable orifice and a pathway from the shock tube to the accumulator. The plunger assembly is slidably coupled to the body assembly and includes a piston. The piston and the shock tube are in slideable relation such that when the plunger assembly is introduced into the body assembly the piston is introduced into the shock tube.
1. A recoil shock absorber for a firearm, the recoil shock absorber comprising:
a body assembly configured to be installed in a stock of the firearm, the body assembly including:
a shock tube including an opening at a distal end;
a cylinder end rotatably coupled to the shock tube at the distal end of the shock tube, the cylinder end including a tapered protrusion configured to be adjustably aligned with the shock tube opening; and
an accumulator chamber coupled to the cylinder end, the shock tube arranged on a first side of the cylinder end and the accumulator chamber arranged on a second side of the cylinder end, opposite the first side, alignment of the shock tube opening with a part of the tapered protrusion forms a resulting orifice and pathway from the shock tube, through the cylinder end, and to the accumulator chamber;
a plunger assembly slidably coupled to the body assembly, the plunger assembly including a piston at a proximal end of the shock tube, the piston and the shock tube being in slideable relation such that when the plunger assembly is introduced into the body assembly the piston is introduced into the shock tube; and
a return spring coupled to the piston and the shock tube.
2. The recoil shock absorber as in claim 1 , wherein the shock tube opening is aligned with the part of the tapered protrusion by rotating the shock tube using an interface at a proximal end of the plunger assembly.
3. The recoil shock absorber as in claim 2 , wherein the shock tube is configured to be rotated using a choke key.
4. The recoil shock absorber as in claim 1 , wherein the tapered protrusion tapers from a first depth to a second depth, the first depth being less than the second depth.
5. The recoil shock absorber as in claim 4 , wherein the first depth is approximately zero and the second depth is approximately equal to a size of the shock tube opening.
6. The recoil shock absorber as in claim 1 , wherein the cylinder end includes at least one return path with a check valve.
7. The recoil shock absorber as in claim 1 , further including an over-pressurization relief vent configured to vent excess pressure to the accumulator chamber while allowing the recoil shock absorber to continue to function as a shock absorber.
8. The recoil shock absorber as in claim 1 , wherein the return spring comprises a mechanical spring element configured to provide a progressive force rate over a linear stroke of the recoil shock absorber.
9. The recoil shock absorber as in claim 1 , wherein the return spring comprises multiple mechanical spring elements, each mechanical spring element is configured to provide a force rate over a linear stroke of the recoil shock absorber that is different than a force rate of any other of the multiple mechanical spring elements.
10. The recoil shock absorber as in claim 9 , wherein at least one of the multiple mechanical spring elements is configured to provide a progressive force rate over the linear stroke of the recoil shock absorber.