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Shot deer

40 Cal
Joined
Feb 1, 2019
Messages
345
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246
Location
Northern ohio
I have a Connecticut Valley Arms (CVA) Mackinaw rifle in 50 Cal.
Every so often when I (try) to to cock it, I pull it to full cock, and instead of staying like that, it slams forward as if I fired it. I don't have my finger on the trigger or blocking anything. To make it work I squeeze the trigger and fiddle with the hammer, and after a minute or so of that it will catch. Have any of you had this problem, and if so how did you fix it (if you did). Any advice will be appreciated!
 
I have a Connecticut Valley Arms (CVA) Mackinaw rifle in 50 Cal.
Every so often when I (try) to to cock it, I pull it to full cock, and instead of staying like that, it slams forward as if I fired it. I don't have my finger on the trigger or blocking anything. To make it work I squeeze the trigger and fiddle with the hammer, and after a minute or so of that it will catch. Have any of you had this problem, and if so how did you fix it (if you did). Any advice will be appreciated!
It sounds like your fly might be sticking. When was the last time you lubed the lock internals?
 
I bought it used about four months ago. I cleaned and lubed it that night, and shot it the next day. Cleaned and lubed everything again. About two months ago I lightly lubed it again because it was doing that weird thing, and it did it again yesterday. What do you think?
 
I bought it used about four months ago. I cleaned and lubed it that night, and shot it the next day. Cleaned and lubed everything again. About two months ago I lightly lubed it again because it was doing that weird thing, and it did it again yesterday. What do you think?

Several things to check, pull the lock and see if the sear is moving freely for one. If not it could cause such a problem as you describe. Another thing to look at is most CVA locks have a sear engagement screw that allows you to reduce sear engagement with the tumbler. If in too far you might not have solid sear engagement. Also look for signs of compressed wood from contact with the lock parts, especially the sear. It's not uncommon for locks to seat deeper over time from being removed and re-installed (often people tend to over-tighten the lock screws too). This can cause the sear to drag and not engage the tumbler freely. If you were going to the half cock position I would suspect the fly but it shouldn't interfere with the full cock position.[/QUOTE]
 
As above.... or....

Take the lock out. Shoot it with break cleaner and allow to dry completely. Repeat. Then shoot it with compressed air. Now just put a drop of oil in the tumbler and a small drop on the fly. That should do it..... I hope. Sometimes that fly will get just a bit of "gunk" on or around it and it does not move as freely as it should.

I have had no less then 4 CVA's brought to me this past fall with the same problem. After checking the wood thing and the sear adjustment this is what fixed it.

JMHO
 
As above.... or....

Take the lock out. Shoot it with break cleaner and allow to dry completely. Repeat. Then shoot it with compressed air. Now just put a drop of oil in the tumbler and a small drop on the fly. That should do it..... I hope. Sometimes that fly will get just a bit of "gunk" on or around it and it does not move as freely as it should.

I have had no less then 4 CVA's brought to me this past fall with the same problem. After checking the wood thing and the sear adjustment this is what fixed it.

JMHO


I will try that. I will tell you if it works.
 
I like use powdered graphite on the lock, especially in the cold months, to keep them functioning properly. I completely clean the lock with brake cleaner, blow it dry with the air compressor, and squirt a few puffs of powdered graphite on the lock for lubrication. Has worked well for me for 30+ years.
 
That lock doesn't have a "fly",, it's the Spanish simple lock;

HPIM0500.JPG

See that screw in the tumbler?
Turn it "up" or "out" (lefty loosey),, it does require fine tuning,, AND,, that screw has been known to "strip". If it won't stay in position after adjustment and/or repeated adjustment is needed, you'll need a new tumbler,, ($20 at Deer Creek)
Here's another photo of the same screw but in the Spanish bridled lock;

HPIM0673.JPG
 
Did necchi's advise help?

Something is causing the sear to be pushed out of the full cock notch. First step is the sear engagement screw necchi described. The second line of possible interference is that the trigger plate is pulled too deep into the trigger plate mortise. A shim above the trigger plate may be required to get a little bit clearance between the trigger lever and the sear.
 
Did necchi's advise help?

Something is causing the sear to be pushed out of the full cock notch. First step is the sear engagement screw necchi described. The second line of possible interference is that the trigger plate is pulled too deep into the trigger plate mortise. A shim above the trigger plate may be required to get a little bit clearance between the trigger lever and the sear.


I'm thinking that is the problem, when I get a chance I'm going to do that.
 
Another possible issue, common on some CVA locks. The nose of the sear gets broken off and may not be real apparent until you look closely at it. This will keep it from engaging the full cock notch correctly.
 
I have a Connecticut Valley Arms (CVA) Mackinaw rifle in 50 Cal.
Every so often when I (try) to to cock it, I pull it to full cock, and instead of staying like that, it slams forward as if I fired it. I don't have my finger on the trigger or blocking anything. To make it work I squeeze the trigger and fiddle with the hammer, and after a minute or so of that it will catch. Have any of you had this problem, and if so how did you fix it (if you did). Any advice will be appreciated!
After removing your lock from the stock does the problem still remain? If the lock functions correctly out of the stock then the problem may be the sear rubbing on wood or the trigger group needs adjustment or is inletted too deep. Soot up the end of the sear and reinstall. Then remove to see if the sear left a soot mark on the wood. If so carefully remove a small amount of wood and retry until there is no soot transferred to the the wood. Good luck.
 
or the parts binding on wood in the bottom of the mortise as brawny suggested. Sometimes, with a cva, you can tighten the lock bolts too far and cause the binding. If that is the problem, it can be corrected easy enough, but requires a little know how for where to build up the interior mortise edges
 
or the parts binding on wood in the bottom of the mortise as brawny suggested. Sometimes, with a cva, you can tighten the lock bolts too far and cause the binding. If that is the problem, it can be corrected easy enough, but requires a little know how for where to build up the interior mortise edges

Yes, very possible that is the problem. To find if there is binding or rubbing, take the lock out and examine the mortise in various light angles. If the lock is rubbing you should see spots on the wood that are shiny. Use a small scraper or chisel to take away some wood. Be cautious, not too much at first. Replace the lock but do not overtighten. Try again, remove again and examine the wood again. Repeat until you are satisfied it is not binding anymore.
 
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