How do you tune a set trigger?

[Harry Marinakis]

I have a new custom squirrel rifle with a small Siler lock, and I have not been satisfied with the set trigger (brand unknown). I could just take it back to the gun builder, but I want to learn how to do this stuff myself.

Adjusting the trigger set screw doesn't change the front trigger pull at all, which has been a source of frustration. I have adjusted the set screw from all the way in to all the way out, and everything in between, but that that doesn't change anything.

Now the hammer won't stay up in the cocked position. Again, adjusting the set screw doesn't fix the problem. Pulling the set trigger first also doesn't keep the hammer up.

The main spring and sear spring are new and in good shape. The lock is clean and lubricated. The lock functions properly when it is removed from the rifle. The sear properly and securely engages the tumbler at half cock and full cock.

I have looked at YouTube videos, and there's nothing useful there.

Do I just need to file down the set trigger plate where it contacts the sear?
Do I need to knock out the trigger mechanism and see what's going on?

 

[The Crisco Kid]

I don't have the answer to the problem but don't touch anything with a file until you get the problem figured out.

 

[wayne estes]

Take some power out of the trigger main spring. Just back the screw on the spring a bit and try it. When you get it where you like it add locktite or nail polish.
I hope this helps.
W

 

[wayne estes]

There’s a sweet spot, with some patience you’ll find it!

 

[Tom the Tinker]

Against my better judgement, I'm going to chime in. I am not knowledgeable about set triggers except for one thing that happened to me a couple of weeks ago. I was checking out a rifle I had recently acquired. The front trigger was difficult to pull. I tried too hard and then nothing worked. The cock would not engage and hold. I took the set triggers out of the rifle and began trying to see if I could figure out how they should work. Then I noticed a small wire laying on my workbench where I had removed the triggers. This small wire fit into two tiny holes on the trigger frame and the rear trigger. After fiddling with it to discover how it fit and engaging it, the triggers worked as they should. Check the little wire spring to make sure it is in place.

 

[Grenadier1758]

With the lock out of the stock, look through the hole where the sear lever goes to ride over the trigger levers. Can you see trigger levers? The trigger levers should be below the sear lever. The first adjustment should be to lower the rear trigger lever to be below the sear lever. Generally, this will be the heavy mainspring. Once the real lever is adjusted to allow the sear lever and the nose of the sear to enter the notches in the tumbler, the other trigger adjustment screws can be turned for adjustment of the trigger pull. @Harry Marinakis's builder should have completed the adjustment of the triggers before delivery.

 

[Grenadier1758]

With the lock removed can the triggers be set? If the triggers can be set with the lock removed, can the set trigger tension be adjusted?

Review the adjustment instructions for the L&R set triggers. Most set triggers will be adjusted the same way.

Some important warnings to adhere to are the adjustments are to be made with the triggers unset.

https://lr-rpl.com/diagram-of-parts-trigger/

 

[Harry Marinakis]

With the lock out of the stock, look through the hole where the sear lever goes to ride over the trigger levers. Can you see trigger levers? The trigger levers should be below the sear lever. The first adjustment should be to lower the rear trigger lever to be below the sear lever. Generally, this will be the heavy mainspring. Once the real lever is adjusted to allow the sear lever and the nose of the sear to enter the notches in the tumbler, the other trigger adjustment screws can be turned for adjustment of the trigger pull. @Harry Marinakis's builder should have completed the adjustment of the triggers before delivery.

So I file down the tip of the mainspring where it touches the tumbler to lower the set trigger plate so the sear can fit in the notches.

I've already driven 90 minutes to have builder tweak the set trigger. He fiddled with it for an hour, but the repair didn't last very long. I don't want to keep driving 90 minutes one way every time I need the set trigger adjusted.

 

[Harry Marinakis]

Review the adjustment instructions for the L&R set triggers. Most set triggers will be adjusted the same way.

https://lr-rpl.com/diagram-of-parts-trigger/

These instructions don't work, my main spring doesn't have an adjustment screw.

 

[Grenadier1758]

There is a screw on the trigger plate that applies tension to the trigger lever. Turning that screw can raise or lower the trigger lever. No filing on the mainspring is required. At this point, all adjustments are to the triggers and the location of the trigger plate. There may be an adjustment to the sear spring tension in the lock. Need to see a picture of your triggers and the lock.

 

[Harry Marinakis]

There is a screw on the trigger plate that applies tension to the trigger lever. Turning that screw can raise or lower the trigger lever. No filing on the mainspring is required. At this point, all adjustments are to the triggers and the location of the trigger plate. There may be an adjustment to the sear spring tension in the lock. Need to see a picture of your triggers and the lock.

That's the problem, turning the screw doesn't do anything.

 

[Grenadier1758]

These instructions don't work, my main spring doesn't have an adjustment screw.

Those L&R instructions are to the trigger plate. The triggers will need to be removed to adjust that trigger plate screw.

 

[Harry Marinakis]

Those L&R instructions are to the trigger plate. The triggers will need to be removed to adjust that trigger plate screw.

Got it. I need to knock out the pin and remove the trigger.

 

[Tumbledown]

Do you know what brand set triggers they are? Can you post a picture of the assembly?

 

[Grenadier1758]

@Harry Marinakis here is another description of the operation of double set triggers. This also shows the relationship of the trigger levers to the sear lever.

https://cdn.trackofthewolf.com/Pdfs/catalog/page_352.pdf