Russ Hamm Mainspring

[oldarcher]

I recently purchased a very nice longrifle at a Civil War show. It is well made and nicely carved and has a DOUGLAS GAA 44" .45 1-48 twist barrel. Unfortunately it has a Russ Hamm caplock. This one was made later by Dean Mitton and although it is OK it is NOT my favorite lock.  The problem that I really need to deal with is the mainspring. It works OK but is a little weak. I would rather replace it than try to retemper it. If I could find one it would be great...I know that the lock has been copied by the Spanish gun makers for export to us, and I also understand that L & R makes a replacement? Any help and advice would be appreciated as I really would like to shoot this rifle regularly.
Thanks

[Dphariss]

Polish the spring.
Clamp the upper arm or the bend in a vise.
Clamp small Vise Grips to the end of the lower leaf and carefully flex the spring to add 1/4 to 3/8" more preload.
Carefully heat keeping the torch moving so the color changes full length of the leaf  about the same time. When it hits blue the tension needed to hold the flex will relax. Stop heating and let cool a few seconds. When the spring is cool try it in the lock.
Worst that can happen is the spring was not hardened properly to begin with or you anneal it. I never order a spring if I can fix the one I have.
Ordering 1. Takes too long.  2. The one I get may be worse than the one I have. So its easier to fix the one I have if possible.

Dan

[EC121]

Dixie Gun Works carries a selection of lock springs.  Or put a shim under the lock plate end of the spring.

[Bob Roller]

See if L&R has a replacement for this lock in their RP-L series.
The Hamm lock was similar to a CVA of that time frame.

Bob Roller

[Mark Brier]

If you can obtain a replacement spring that would be the easiest. If not determine how much of the foot of the spring is on the toe of the tumbler. If you have the length in the spring that would be good. Start with  annealing the spring. Then put some pre-load in the spring it shouldn't take a lot, probably no more than an 1/8inch and re-temper. If you had enough length in the spring you should be able to use the same hole in the lock plate if you're lucky. If not you may need to plug the hole in the lock plate and relocate. Not a big either I have seen plugged holes in original work either from the initial building or from repairs such as this.

Mark Brier

[T*O*F]

It works OK but is a little weak.

What does that mean? 
If it works OK, why fool with it?
Sounds like a make-work project to me.

L&R's RPL lock is a replacement lock, not a replacement spring.
It is also not a drop-in replacement, but replaces several different but similar locks.

[Hungry Horse]

 I have no experience with the Russ Hamm lock, but have WAY to much experience with the CVA, and other Spanish copies, of his locks. Most of these locks have a spring that is more than adequate for the task. The problem often is the different hardnesses of the lock parts, and the sloppy fit of the tumbler through the plate. Wear over time creates a bind that the strongest spring in the world can't overcome. A stronger spring only speeds up the wearing process, and soon you are right back where you started. This is why locks made of quality materials, hand fitted by experienced lock makers like Bob Roller, and a very few others, cost so much.

                      Hungry Horse

[B Shipman]

Go the Dphariss route first. This is not hard. Your best bet, and it's free.

[Bob Roller]

Hungry Horse,
Many years ago I was at the Log Cabin Sport Shop in Lodi,Ohio
and saw a boot box full of Russ Hamm's locks that were going back for
repairs.Some failed before being used while being handled by the owner.
I remember a conversation with Russ Hamm at Friendship in 1964 and
he told me I was crazy for taking all the time I did to detail a lock. I told
him I prefer to make a FEW that might actually work than a long line of clunkers
that had my name associated with profane utterances. He said nothing after that.
The man that took over his operation fared no better. The Maslin parts I think are still available from
Jerry Devaudreuil in Wooster,Ohio.He MIGHT have mainsprings for these as weall as frizzen springs.
His phone# is:1-330-234-4500.He has NO E mail and wants none.

Bob Roller