Bill Calfee
Gun Fool
Friend Az_Speed
Friend Az and CYA friends:
Since Az asked for a description of the various parts of the DiOrio 3 lever trigger, I addressed the title of this thread to him.
I'm going to attempt to explain some things about how a three lever triggers produces its lightness of pull...
And then some very interesting things about how this relates to the new V-3 action, especially the way I've got mine set-up.
Here's a doodle...
_______________________________
On a factory Remington trigger, a sear surface about in the middle of the transfer bar contacts the sear surface of the L shaped sear directly...
So you have the cocking piece contacting the transfer bar at the rear, with the pivot pin of the transfer bar at the other end, front, and the sear contact point of the transfer bar about mid way between these two points.
Fulcrum wise, this is like a nut cracker arrangement....
Therefore, if you have a 23# firing pin spring, the actual down force on the top of the L shaped sear may be close to twice that great.
So when you pull the trigger it takes effort to disengage the sear engagement points.......this is why the factory triggers have such heavy pull.
______________________
Then comes the 3rd lever.
If you look at the doodle, you'll see that the fulcrum ratio from the pivot pin of the third lever, to the contact point of the transfer bar, to the tip of the 3rd lever resting on the L shaped sear, is 3.40 to 1............or 1 to 3.40......
Therefore, if we have 23 pounds of firing pin spring pre-load, the actual down force by the tip of the third lever on top of the L shaped sear, is a about 6.8 pounds.
Now, this is where it gets good because of my V-3 having just slightly over 8 pounds of firing pin spring pre-load:
I only have about 2.45 pounds of down force on top of the L shaped sear in my trigger.
Some of you folks should check my math, but, I believe it to be in the ballpark of being correct.
Your friend, Bill Calfee
Friend Az and CYA friends:
Since Az asked for a description of the various parts of the DiOrio 3 lever trigger, I addressed the title of this thread to him.
I'm going to attempt to explain some things about how a three lever triggers produces its lightness of pull...
And then some very interesting things about how this relates to the new V-3 action, especially the way I've got mine set-up.
Here's a doodle...
_______________________________
On a factory Remington trigger, a sear surface about in the middle of the transfer bar contacts the sear surface of the L shaped sear directly...
So you have the cocking piece contacting the transfer bar at the rear, with the pivot pin of the transfer bar at the other end, front, and the sear contact point of the transfer bar about mid way between these two points.
Fulcrum wise, this is like a nut cracker arrangement....
Therefore, if you have a 23# firing pin spring, the actual down force on the top of the L shaped sear may be close to twice that great.
So when you pull the trigger it takes effort to disengage the sear engagement points.......this is why the factory triggers have such heavy pull.
______________________
Then comes the 3rd lever.
If you look at the doodle, you'll see that the fulcrum ratio from the pivot pin of the third lever, to the contact point of the transfer bar, to the tip of the 3rd lever resting on the L shaped sear, is 3.40 to 1............or 1 to 3.40......
Therefore, if we have 23 pounds of firing pin spring pre-load, the actual down force by the tip of the third lever on top of the L shaped sear, is a about 6.8 pounds.
Now, this is where it gets good because of my V-3 having just slightly over 8 pounds of firing pin spring pre-load:
I only have about 2.45 pounds of down force on top of the L shaped sear in my trigger.
Some of you folks should check my math, but, I believe it to be in the ballpark of being correct.
Your friend, Bill Calfee