Question on single phase double set triggers

[far55]

I am getting ready to start on a southern mountain rifle and have been considering making a set of triggers using Ken G. s tutorial here in the general discussion section.  I do not want to set the trigger before cocking the lock. The triggers I have used and handled have full spring pressure through the entire travel that would transfer to the sear and prevent doing this. Would the design of the rear trigger  with some extra mass on the top of the trigger and the spring bottoming out on the plate sooner allow enough inertia to trip the sear ? In other words, I would like some free travel beyond the spring tension so it would settle back into place below the sear contact point to relieve pressure on the sear. Can anyone help me out here, am I looking at this right ?  Thank You,  Roland

[Daryl]

Look at a set of double set, double throw triggers.  The double set, single throw trigger could be made identically, except for not having the tripping blade on the front trigger, could it not? It would then act exactly like any double set, single throw, except the hammer could be cocked before setting the trigger.  The cock could then be let down, by holding the cock and pushing forward on the rear trigger, seems to me, instead of having to set the trigger, then firing and catching the cock.

[Bob Roller]

I've made ONE set of these single phase triggers in the past 40 or more years
and Taylor got them. I adjust them by shortening the tip of the mainspring that
drives them up and making the rear trigger a floater that strikes and releases
the sear and then drops back down.
Daryl is right about lowering the cock or hammer by holding cock or hammer back and
pushing the rear trigger forward to let it down.

Bob Roller

[Ian Pratt]

Roland - since you are thinking of making your own set triggers, you have the advantage of being able to "design out" problems like that. If you know the distance from the outside of your trigger plate to the bottom of the sear, you can use that to plan the height of your rear trigger blade where it will contact the sear. Make your trigger blade a little taller than this to start. When your triggers are ready to try out, drill and tap your plate to install a machine screw (temporarily ) that will come up from the outside of the plate and bear directly on the bottom of the mainspring about 1/3 of the spring's length back from the tip. You turn this screw in slightly which lifts the mainspring tip slightly off it's seat allowing the nose end of the trigger to drop. When done properly you use it to tune your rear trigger's height so when at rest it will not contact the sear, but you'll still get enough mainspring power to trip the lock. You may need to also remove a little more stock from the top of your trigger blade to get things balanced.

After you find the right adjustment of this screw, remove the spring so you can measure the length from the inside of the trigger plate to the tip of the screw where it was contacting the spring. Counterbore your plate to the size of the screw's head and run the screw in tight, then reduce the height of the protruding shank to the length you just measured. Flush off the screw head to the surface of the plate. Now you know why some old trigger plates show the remains of a screw slot in the plate. 

[far55]

Thank You all for your responses. I think the adjusting screw idea is exactly what I was looking for, Roland

[Curtis]

Some great info there Ian, thanks!

Curtis