Binding Lock Internals

[BigSkyRambler]

I am having fits with a custom SMR. While the cock is out of the rifle, it goes to both half and full cock.  When in rifle, it won't engage half cock.  Something is binding.  I have started slowly removing wood from the lock mortice, but am flying blind, as I have not had to do this before.  Problem may explain why the rifle was unfired when I got it  . where should I focus my attention?

[rich pierce]

Often one of 2 things is happening.
1) The trigger blade is too tall and not letting the sear drop fully into the half cock notch.
2) the sear arm is being limited in its motion by wood in the hole. 

[bluenoser]

I agree with Rich.
I recently repaired a rifle with a similar problem for a friend.  The hole for the sear bar was not quite deep enough and the end of the bar was bottoming out.

[BigSkyRambler]

Thanks! I'll try opening up the sear bar hole tomorrow.

[smylee grouch]

A rat tailed file on the bottom of the hole might be just enuf to do the trick. Just keep inside the lock mortice. 

[Eric Krewson]

Black the inside of the lock with candle soot, the parts will mark where you need to remove wood.

[Pukka Bundook]

What Eric says,
You only need to remove wood where its needed, not doing it blind.
  Prussian blue, candle soot or similar, assemble and work it, dismount and look for marks, BigSky.

[Daryl]

I think maybe erasable felt pen might also be a good one for this. It is wonderful on dulling shiny sights,
 as it is flat black like soot and like soot, it is easily wiped off from objects. It is probably the easiest of all to apply.

[kutter]

Remove the trigger from the rifle. The place the uncocked lock back into the stock and see if it can be cocked back to 1/2 and then full cock with out any problems.
If the lock works fine with the trigger out of the way,
then it's the Trigger Blade that is likely too high and not allowing the sear bar to drop low enough so the sear nose engages at 1/2 cock.

If there is still a problem, then clean all the surfaces of the wood inside the lock inlet with alcohol or acetone so you have as  clean&  brite wood as possible.
Then smoke/soot or otherwise color the metal lock parts and then carefully lower the lock back into place and pull the hammer back once again to allow the offending area to be marked.
I would use something like Red LipStick for a color marker this time around so you can absolutely see the difference betw old inletting marks and this new obstruction.

[gusd]

Also, make sure sear hole is deep enough.
Difficult to see.
Gus

[Pete G.]

Don’t overlook the sear arm touching on the end. (another way of saying what Gus just said)

[smylee grouch]

That sear arm touching in the bottom of the hole is some times hard to see but since the trigger blade usually contacts the sear toward the center of the sear a SLIGHT grind on the end of the sear might be enuf to make it clear the wood.

[Darkhorse]

Sounds like some lock parts aren't fit correctly. Out of the rifle see if you can see the top of the fly, cock it and see if the bind is there. If the fly is too tall the sear will not be able to ride over it and it will bind up when cocking. If so the fly needs to be fit with swiss files.
I would suggest sending the lock to someone who really knows what he's doing and having him tune it. Not only will the lock actually work but it will be much smoother and faster.

[steven baker]

Over tight tang bolts and lock bolts can cause issues if all else fails, take care Steven,

[WKevinD]

I wish you lived nearby I think this could be solved in short order...and you would buy the drinks.

Kevin

[JTR]

Looks like BigSkyRambler has ducked out.....

Hasn't posted on this thread in 2 weeks now....