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mountainman
06-21-2013, 01:23 AM
Here is one I haven't encountered. I bought a cheapy cva made in spain rifle with a percussion lock. When I go to the half cock position it will fire if you pull the trigger. When I pulled the lock everything was clean and sharp and it went to the half cock notch and locked perfectly. I did a little bit of inletting to make room and I also worked the trigger thinking that one or both of these were the problem. Well I put the lock back in and the same thing happens. I removed the lock again this time in the half cock position and found the sear to be resting on top of the half cock groove instead of locking up. This was a kit gun and of extremely low quality (some one did not do a very good job of fitting and finishing) But I figured for the price I would atleast have a shooter or enough parts to do something else. I had a post here a while ago about making this into a flint lock but the dollars aren't woth it. Any help is greatly appreciated. Thank you

waksupi
06-21-2013, 01:29 AM
Sounds like you still have some wood interference on the sear. Also, assuming it is a single hung trigger, there should be just the slightest amount of slop before it engages the sear.

rhbrink
06-21-2013, 06:04 AM
Bet the top of the trigger is riding on the bottom of the sear which will not allow the sear to rotate fully into place. If you pull the hammer all the way back to the full cock position I'm thinking that the hammer does not engage in anything and will fire if released. IF this is the case you will need to remove the trigger and file some of the top off to get clearence as waksupi suggested you need a bit of play between the trigger and sear.

RB

gon2shoot
06-21-2013, 08:09 PM
Wood fit could well be the problem, had one that that was slightly "sprung".

oldracer
06-21-2013, 09:05 PM
If you want to replace any parts, I would suggest contacting muzzloader's supply company as they carry a lot of very well made locks, triggers, sights and everything else you might need. They also carry barrels of all types, etc, etc, etc. I bought all the parts for my Lehigh 42 inch barrel M/L that can hit a standard NRA 3 bulls eye target at 3 hundred yards! It is the parts, surely NOT me.

fouronesix
06-21-2013, 10:18 PM
Yep, seems to be a fairly common problem with this type ML. Hard to give an absolute answer and the previous posts pretty well cover where to start. Also, as others have posted, relieve any wood contact with the moving parts. Then, also as others have posted, check the trigger plate to sear bar contact- there should be some clearance between the two when in the full cock position (the trigger should wobble ever so slightly back and for).

Take a little off the trigger plate where it contacts the sear bar with a small grinder/sanding drum. Then hone smooth the contact area. Take a little off, check function, repeat until you can tell if it helps the sear have continuous "sliding" contact with the tumbler (and notches) as the hammer is rotated rearward. While the lock is out, also check to make sure the small hairpin sear spring is operating correctly, smoothly and not contacting wood- it's what keeps the sear in contact with the tumbler as the hammer (tumbler) is rotated rearward.

Trigger pull (over travel) is what keeps the sear from contacting the half cock notch as the hammer rotates forward when firing- if the tumbler doesn't have a fly. If it has a fly then the fly primarily keeps the sear clear of the half cock notch during forward rotation.

bubba.50
06-21-2013, 11:04 PM
i had a cva mountain rifle with a similar problem. turned out to be that the trigger inletting was too deep allowing triggers to put enough pressure on the sear that it didn't fully engage the 1/2 cock. shimmed the trigger-plate & the problem went away.

luck & have a good'en, bubba.

mountainman
06-25-2013, 12:06 AM
Thank you all I'll be working on it this week end. There is no play at all in the trigger so hopefully that will fix the issue.Thanks again
Craig

bigted
06-25-2013, 12:22 AM
just a small bit from a fellow shade tree craftsman to ensure you will work on the correct thing there...do the shimming thing with say tablet backing under the trigger plate first to see if this allows everything to function before you start removing metal...metal is a bunch harder to replace then wood and will make those cuss words come a bit harder if you ensure what the problem is first... just my thoughts from a feller that has been there...done that...:wink:

junkpile
06-25-2013, 09:53 AM
I'm with Bubba and Bigted on this one. I would actually suggest dropping the trigger out entirely first, and seeing if the half cock works. If you still have problems, you have more investigating to do. If it works, you know it's the trigger.

Then shim the trigger assembly and see what you've got. If still good, it can be shaved down, and the shim(s) removed.

mountainman
06-26-2013, 03:43 PM
just a small bit from a fellow shade tree craftsman to ensure you will work on the correct thing there...do the shimming thing with say tablet backing under the trigger plate first to see if this allows everything to function before you start removing metal...metal is a bunch harder to replace then wood and will make those cuss words come a bit harder if you ensure what the problem is first... just my thoughts from a feller that has been there...done that...:wink:
Good call on that one. I've not thought about doing that. I'm going to work on it on tomorrow I'll let you all know if it works. Thanks again
Craig

izzyjoe
06-26-2013, 10:17 PM
The trigger should have a little play in it, before it touches the kickoff bar.

mountainman
06-30-2013, 11:32 PM
Well I did some more inletting and I also took about 1/16th of an inch off the trigger and everything worked great. For a cheap rifle it shoots well I'm figureing it shoots better than I am able. Thank you all for your info.
Craig