Double set double phase trigger issues

[TerryK]

I used this trigger for a bit less than 400 rounds. Now with great frequency the front trigger is "set" without using the rear trigger. If you pull on the rear trigger is does nothing to set the front trigger since it is set. If I lower the cock, and pull it back to fire sometimes it will eneable the rear trigger so I can set the front trigger. I tried adusting the bottom screw between the triggers, and tried the main spring screw also.
My guess is the "side" spring is weak. When I trip the trigger with the front blade, it is not the snappiest I ever saw. Anyway I played with it and I really can't see anything wrong.
So what are some tips, and tips in general for this type of trigger?

 

[Phil Coffins]

When the rear trigger is set the front trigger is mearly a release for the rear to pop up and hit the sear. If the rear isn’t popping up then it hasn’t been set to start with or the spring isn’t applying enough pressure to the rear trigger. With the triggers out of the rifle do you get this snappy action?

 

[EC121]

It is possible that you have worn the front or back trigger latching edge by setting it too fine. That would let it round off and slip off now and then. As Phil said the front trigger doesn't "set". It just latches the back trigger blade down to let it snap up when the front trigger is pulled. The front trigger blade will trip the sear like a single trigger. While triggers are out, look for shiny or dark spots in the trigger inlet. Something might be rubbing or the wood has compressed.

 

[TerryK]

I have it out now, and it operates normally, but when fired, I think it is kinda weak popping up.

Naturally the problem is hard to recreate out of the stock, because a key issue is at full cock the rear trigger is not clicking, and the front trigger is already set. So the front trigger sets on cocking. Seems unsafe to me.

 

[Phil Coffins]

I’m having trouble following your problem so to clarify, with the triggers in the rifle can you feel any wiggle fore and aft of each trigger at fired, half cock and full cock?

 

[TerryK]

I don't have the trigger in the rifle because I expect to return it.
When I pull back the cock to firing position, the rear trigger wont move. The rear trigger seems like it has been pulled to the rear, but I never touch it. The front trigger is set in the hair position though. So the rear trigger is disabled. In this state, I have a trigger that has automatic hair front trigger only on cocking.
This condition happens 50% of the time. The other 50% it functions normally.

Out of the rifle it works normally, with the rear trigger being able to set the front trigger. I can also use front trigger with being set. So it works in both set and unset normally.

 

[Phil Coffins]

Your trigger assembly is too high, the rear trigger should always have some play in it (except when you set it) indicating that it not touching the sear.

 

[IanH]

I've never seen a sear spring strong enough to set a hammer trigger when the cock is pulled back through the notches. Usually they fight each other and the hammer trigger spring wins, holding the sear up and making it so the lock can't be cocked at all in the case that the hammer trigger is set too high and/or the spring needs a stop or the tip filed so it doesn't force the hammer trigger up so high against the sear arm.

The hammer trigger spring needs to be strong but only applying force on the hammer trigger until the hammer trigger almost touches the sear, then it should contact through inertia only. Many rifles aren't built properly and the hammer trigger shoves up on the sear bar all the time, or just enough to keep the sear from setting properly at full cock which is a dangerous condition. The front trigger should only either catch and hold the hammer trigger when the hammer trigger is manually pulled all the way back, or if the hammer trigger is not set, the front trigger should be able to fire the lock by just pulling it.

Basically, no part of the trigger assembly should ever touch the sear bar unless a finger is touching the front trigger to either release the hammer trigger or manually fire the lock.

 

[Roy Gearhart]

It sounds to me like when you cock the hammer that the sear on the lock is setting the rear trigger. As someone else has said, that means your dear spring must be pretty stiff because the trigger normally would hold up the sear so that the lock would not catch. That would also indicate that the main spring on the trigger is set up very light, probably too light to trip the lock.
As someone else mentioned, there should be some play between the lock seat and the triggers, even when unset. Several things may be going on that need to be worked out by an experienced builder. I doubt that a new set of triggers will fix the issue.

 

[TerryK]

While I had it out, I disassembled and cleaned and oiled it up a bit. I think I found the issue maybe??

If I use the front trigger, it compresses the small side wire spring. If I do this the spring hangs up on the front of the trigger frame and never goes completely up to put pressure on the front trigger. If I push up on that spring it goes up maybe .015 and will allow the rear trigger to catch in the front trigger. it will work this way correctly, until the small spring sticks, and does not push up all the way.
So the side spring is sticking low and not pushing fully up to position the front trigger to catch the rear trigger.
I guess it needs a new spring, or a bit of metal removed from the trigger frame to allow the spring to fully rise.
I kinda don't want to remove any metal until I see what Jim Kibler has to say. He built this rifle in the white, so he did all the fitting. I imaging this has happened before. I called yesterday, but they said it is busy due to the Christmas rush to ship, and i fully understand that. Flintlock deer season starts a week from now, so it is bad timing.

 

[TerryK]

Since flintlock hunting is a week from today, I figure I should try to file off a bit of the trigger frame.
New triggers are 70 bucks, so with hunting approaching is is worth the risk.
The spring would catch/drag right at the top of the spring travel.
So I took off a burr and did a radius the top using a jewelers file. Then I smoother it out with 500 and 2000 grit wet and dry sand paper. Now the spring rides without any drag and no hesitation bump. Funny how such a small amount of metal was causing the issue. Anyway it really looks solid now, and I did a full assembly and it works great. Good opportunity to learn.
If you look at the spring in the pictures, top pic shows spring below burr, the lower pic shows where it would catch on the (edge) burr.

 

[reddogge]

If you need more muscle in the rear trigger to trip the sear, tighten up the rear screw on the rear spring.

 

[TerryK]

I have a pretty fair amount of tension on the rear main spring. It is a lot more snappy when I cleaned and lubed everything up.
I just shot 20 rounds, and I never has the set trigger issue.
So I am pretty confident it was a machining burr on the trigger frame that held up the reset spring.. The set trigger spring does not drag and hesitate after the deburring. So now the spring can pivot the front trigger to catch the rear trigger.

 

[James Kibler]

This all is very difficult to follow and diagnose from afar, but why don't you just send the trigger back and we'll check things out and fix anything that isn't right. No charge.

All the best,
Jim

 

[Flintleather]

This all is very difficult to follow and diagnose from afar, but why don't you just send the trigger back and we'll check things out and fix anything that isn't right. No charge.

All the best,
Jim

Now that is Great customer service!