Firing mechanism for a firearm
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.
1. 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 0.2 inches.
2. The sear of claim 1 wherein the camming surface has a curved surface with a radius between 0.04 inches and 0.06 inches.
3. The sear of claim 1 further comprising a rearward surface of the rearward portion, wherein at least a portion of the rearward surface is configured to engage a firing pin and comprises at least partially a substantially flat surface, and wherein an angle between the at least a portion of the rearward surface and the longitudinal axis of the longitudinal member is between 90.5 degrees and 92 degrees.
4. The sear of claim 1 wherein at least one engagement surface of the sear is polished.
5. The sear of claim 1 further comprising a rearward surface of the rearward portion, wherein at least a portion of the rearward surface is configured to engage a firing pin and comprises at least partially a substantially flat surface, and wherein an angle between the at least a portion of the rearward surface and the longitudinal axis of the longitudinal member is 90 degrees.
6. The sear of claim 1 wherein the camming portion includes a lateral side surface configured such that a trigger bar included in the trigger assembly rests against the lateral side surface after the firearm has been fired.
7. The sear of claim 1 wherein an upper surface of the camming portion is rounded.
8. The sear of claim 1 wherein an upper surface of the camming portion is bull-nosed.
9. The firearm of claim 1 wherein the camming surface includes a radius between 0.03 inches and 0.08 inches.