not holding half cock

[bjarard]

All,
I have a TRS Tower Long land lock that is functioning fine in my hand..ie..holds half cock n...unable to get it to go off in HC. Nice transition to full cock. Buttery smooth. When I place it into the stock I will not hold half cock. Goes off just as if on full cock when I pull the trigger. What is going on? How can I correct this. Pictures are at half cock. I can send more pics if needed. This is frustrating as I tested in the stock earlier and it worked fine. At the end game now...can't believe this came up.

 

[Larry (Omaha)]

Looks like the sear toe is broken off. Get a new sear!
Larry

 

[64Springer]

And your 1/2 cock looks like an 1/8 cock.

Square up and deepen the half cock notch.

Does TRS use drug addled beavers to chew parts to final dimension?

Looks worse than L&R and I didn't think that was possible.

 

[bjarard]

I was able to get the lock to hold at half cock when using just a ruler to push on the sear. This is the trigger. Some red grease showing where the sear moves along its path. Do I need to take more off of the trigger?...or do I have too much off of the trigger (thereby needing a new trigger).

thanks

 

[64Springer]

Picture yourself inside that trigger/sear group.

What is that red grease line telling you?

Think it through some and tell us what you're seeing.

 

[Comfortably_Numb]

Could be wood interference with the sear somewhere too.

 

[bjarard]

Picture yourself inside that trigger/sear group.

What is that red grease line telling you?

Think it through some and tell us what you're seeing.

Take more off

Could be wood interference with the sear somewhere too.

i reapplied inletting grease. Detected nothing

 

[64Springer]

Take more off

i reapplied inletting grease. Detected nothing

I don't know how sloppy your trigger channel/inlet is, left to right, but it looks to me like the tip of your sear bar is riding along the side of your trigger.

There is a radius being formed by the grease.

And if the sear bar is sliding past the trigger, it could be doing it while you're cocking the thing. Binding everything up.

Try shimming the trigger towards the lock plate and see if the sear trips the tumbler. Shimming it may place the trigger under the sear bar.

This also explains why you can trip the mechanism with a ruler. You were able to push on the sear bar.

 

[waksupi]

If it works off the rifle, that usually points to wood interference.

 

[Larry (Omaha)]

I was able to get the lock to hold at half cock when using just a ruler to push on the sear. This is the trigger. Some red grease showing where the sear moves along its path. Do I need to take more off of the trigger?...or do I have too much off of the trigger (thereby needing a new trigger).

thanks

First, you need a new sear. Put the new sear in and determine with dial calpers if the sear bar is long enough to be in the path of the trigger swing. Go from there.
Larry

 

[Commodore Swab]

Install the lock without the trigger or guard. Use a piece of steel to push up and where the trigger should be. Check function. This will tell you if it is wood interference or trigger.

 

[bjarard]

Take more off

i reapplied inletting grease. Detected nothing

This is my first build

I don't know how sloppy your trigger channel/inlet is, left to right, but it looks to me like the tip of your sear bar is riding along the side of your trigger.

There is a radius being formed by the grease.

And if the sear bar is sliding past the trigger, it could be doing it while you're cocking the thing. Binding everything up.

Try shimming the trigger towards the lock plate and see if the sear trips the tumbler. Shimming it may place the trigger under the sear bar.

This also explains why you can trip the mechanism with a ruler. You were able to push on the sear bar.

that radius was just to show the arc of the sear. Trigger sits well under the seat arm

 

[bjarard]

Install the lock without the trigger or guard. Use a piece of steel to push up and where the trigger should be. Check function. This will tell you if it is wood interference or trigger.

Did that. Applied bright red grease…nothing

 

[waksupi]

Did that. Applied bright red grease…nothing

With the trigger mounted, there should be slight play between trigger and sear when cocked and uncocked. I like around 1/16" free play.

 

[bjarard]

Here’s a pic where the trigger is hitting on the seat arm.

With the trigger mounted, there should be slight play between trigger and sear when cocked and uncocked. I like around 1/16" free play.

thanks. I have a little play at both ends

 

[Comfortably_Numb]

You're hitting wood somewhere with the sear.

 

[bjarard]

You're hitting wood somewhere with the sear.

I’ve colored that baby up…put it through its range of motion…nothing. I think I’m going to try a new sear. There is a slight angle at the tooth.

Running out of options

 

[bjarard]

When I pull the trigger at HC the hammer is moving slightly back

 

[54ball]

Get a candle and some optivisors where you can see
Smoke the lock of over the candle...
place the sooted lock in the inlet
Screw the lock down
Cock and uncock the lock
Remove and take a look

Look real close with magnification

 

[54ball]

Another thing to try.....

With the lock installed remove the trigger assembly and guard.

Put the lock in half cock
See if will hold half cock when you apply reasonable pressure on the sear with a punch

This will tell if the trigger assembly is preventing the sear from fully seating in the notch.