Sunday, September 18, 2011

The one hour gunsmith puts a new mainspring in a muzzleloader

The subject of todays project is a CVA Squirrel rifle that was built from a kit back in 1990. Over 20+ years the mainspring has gotten weak. Used only for target shooting witha 45 caliber barrel over those years a miss fire now and then was no big deal. This year I've decided it will be a squirrel killer and I have reinstalled the 32 barrel.

After making sure the gun isn't loaded, place the lock on half cock. Then partially loosen these two screws. when the screws are about half way out give them a light tap with the handle of your screwdriver. This loosens the lock from its mortise. When the lock is loose you can remove the screws completely.

Here is the backside of the lock showing the mainspring. Also shown is a replacement spring. Genuine CVA mainsprings bring $15 and up on ebay and you don't know thier history. The spring shown is a Traditions part. The Traditions spring is wider, but otherwise close enough to be an almost drop in part. It was also purchased at a gunshow new in it's package for under $6. The mainspring vice was borrowed from a friend.
After lowering the spring to it's fired position you can remove the spring. Here is the old spring in the vice. I've been told you should only use a proper mainspring vice to avoid breaking the spring. The new spring however had ideas of it's own. CVA left an oxide coating on thier spring and the vice was able to hold it quite well. The Traditions version was highly polished and between the extra strength and the polish it just kept slipping out of the vice. I ended up using a pair of needle nose locking pliers. Even using the pliers I had to use a file to roughen the surface so it wouldn't fly accross the room.
Here is the lock with the new spring installed. I got lucky and the inletting was sufficient to just reinstall the lock. The new spring was easily 30% wider than the old one. While I didn't have to make room for it, you may have to depending on your gun. Now it takes some serious effort to pull the hammer back. Thankfully this gun has set triggers otherwise I may have had to do some trigger work.
A gunsmith would have charged $30-$35 for this job. It cost me $6 and just over half an hours time.



Gorges Smythe said...

I worked in a muzzle-loading shop for 3-1/2 years. It always amazed me the number of folks who'd pay us to do simple things like you did in these photos. Good job!

woodsrunner said...

Yes I was once one of those guys. Back when good machinists jobs were still around and I had more money than time. Since then really good jobs have gone away, and my favorite gunsmith has retired. When he retired and sold his house and shop, I managed to pick up a big bunch of his books, tools and some spare parts. Now I have time and little money. I also miss working with my hands. Maybe in this case it's better now.

Le Loup said...

Good one.
Le Loup.
A Woodsrunner's Diary.