Firing mechanism for a firearm
AssigneeApex Tactical Specialties, Inc.
InventorRandall M. Lee
Life of this patent
Estimating the term…
Abstract
A firing mechanism for a firearm is provided for reducing maximum trigger pull weight attributable to a sear and for reducing trigger pre-travel and over-travel distances. By this, the likelihood of sear flutter phenomena is greatly reduced while also decreasing or maintaining maximum trigger pull weight. Also, hand movement during firing is reduced helping to increase accuracy.
Claims32
A firearm comprising:
- a trigger assembly;
- a sear configured to rotate between a first pivotal position and a second pivotal position around a fulcrum located in the sear in response to engagement by the trigger assembly;
- and
- a sear spring having a sear spring weight and configured to bias the sear toward the first pivotal position;
- and
- wherein the firearm is configured to produce a maximum trigger pull weight attributable to the sear that is approximately linearly related to the sear spring weight as a function of a line having a slope of between about 0.3 and about 0.7.
A sear for a firearm comprising:
- a longitudinal member;
- a fulcrum opening in the longitudinal member substantially perpendicular to the longitudinal axis of the longitudinal member, the fulcrum opening configured to receive a fulcrum body and to allow the longitudinal member to rotate about the fulcrum body, the fulcrum opening effectively partitioning the longitudinal member into a forward portion and a rearward portion;
- and
- a camming portion disposed on the forward portion of the sear and comprising a camming surface for engagement by a trigger assembly;
- wherein a distance from the center of the fulcrum body to a point of engagement of the trigger assembly on the camming surface is at least approximately 0.2 inches.
A firearm comprising:
- a trigger comprising:
- a trigger face disposed on the front of the trigger;
- a trigger pin opening located near the top of the trigger and configured to receive a trigger pin and to allow rotational movement of the trigger about the trigger pin;
- a trigger bar pin opening configured to receive a trigger bar pin;
- and
- a rearward stop shoulder disposed on a rear surface of the trigger and located near and opposite the vertical center of the trigger face and configured to engage at least a portion of the frame of the firearm to abate rearward rotational movement of the trigger about the trigger pin;
- wherein substantially no additional force is exerted on the trigger bar pin when a rearward force is applied to the trigger and the rearward stop shoulder is engaging the at least a portion of the frame of the firearm;
- and
- wherein a force on the trigger pin is greatly exceeded by a rearward force applied to the trigger when the rearward stop shoulder is engaging the at least a portion of the frame of the firearm.
The trigger of claim 14 wherein the trigger is composed of a substantially inflexible material.
The trigger of claim 16 wherein the trigger is configured such that rotational movement of the trigger about the trigger pin is abated unless rearward force is applied to the safety blade to rotate the safety blade to disengage at least one safety mechanism.
The trigger of claim 19 further comprising a safety blade biasing spring configured to bias the safety blade such that the at least a portion of the safety blade extends forward beyond the forward face of the trigger.
A method of modifying a firearm comprising:
- providing a sear configured to rotate between a first pivotal position and a second pivotal position around a fulcrum located in the sear in response to engagement by a trigger assembly;
- providing a sear spring having a sear spring weight and configured to bias the sear in the first pivotal position;
- and
- wherein, upon installation of the sear and the sear spring into the firearm, the firearm produces a maximum trigger pull weight attributable to the sear that is approximately linearly related to the sear spring weight as a function of a line having a slope of between about 0.3 and about 0.7.
Dependencies are inferred from the claim text.