Rolling Block w/ weakened Mainspring

[Argentino]

Howdy,

I´ve bought a ' 66 Rolling Block chambered in .43 Spanish (Argentine Contract).

Mainspring lost a lot of tension so the hammer will fall weakly over the firing pin (maybe someone kept it cocked for a long, long time-I don´t know for sure).

Wondering if there is a method of getting it back to its original strength (like quenching it in oil and then tempering, or something like that).

Does anyone know how to do this? I can also try to make a new one, but I would prefer to fix and use the original instead.

Thanks,

Argie.

[44man]

I make a lot of springs and it might work for you. Heat cherry red and quench in oil, I use transmission fluid.
Now set your lead pot to get to 600° and set it on the lead. Keep at 600 and let it soak for an hour, then fish it out and set on the pot edge to cool down with the pot.
I have ML mainsprings and frizzen springs going strong after 32 years.
I have stainless aircraft safety wire I hang them with, takes the heat and leaves no cold spots like pliers will.

[waksupi]

Check to be sure your firing pin isn't broke.

[country gent]

If it was left cocked the spring may have taken a new "set" also. It may take a little reforming of the shape to save it. quenching and drawing back may renew it. Not sure on the type of steel but I would let is soak a little at red hot and quench in oil. Then temper and slow cool. I might even drop pots temp 20* every 10-15 mins to around 300* then shut pot off. An extra lead pot filled with sand would be handy here as part can be submerged and left there thru the cooling process.

[44man]

If any reforming is needed, do it before anything else. No sharp bends or scratches.
Lay the spring on paper and draw around it. Some springs can be shaped by hand a little, use the paper drawing to compare.

[Argentino]

Many thanks for your help, guys.

Firing pin is sound but hammer gets to firing position under very little pressure and when released it won´t deliver a blow strong enough to ignite a primer.

I´ve already disassembled the action and cleaned everything inside so there is no dried grease or something similar that might be slowing down the hammer.

I´ll compare it´s shape along another original mainspring to bend it gently if needed.

Oil quenching followed by tempering as described sounds like a very good idea. I´ll give it a try soon.

Thanks a lot for your help.

Argie.

[Mk42gunner]

If the spring needs reshaping, I would anneal it first. In my experience it is better to bend annealed spring steel than to try cold bending one that has taken a set.

Robert

[44man]

If the spring needs reshaping, I would anneal it first. In my experience it is better to bend annealed spring steel than to try cold bending one that has taken a set.

Robert
Yes, good idea. Just heat red and cool slow. I forget a lot and they might have buried the part in lime to cool.

[tacofrank]

Buy a spring from Lee Shaver. He can probably sell you an original or make you one. He's a great gunsmith and a great guy. He is probably the best single shot rifle guy in the country. Rolling blocks are one of his specialties.
http://stores.leeshavergunsmithing.com/

[Geezer in NH]

It is a spring that does not work save money and time and get a replacement. Not expensive.

[John Taylor]

https://www.dixiegunworks.com/product_info.php?products_id=5542&osCsid=09q381psbuujul8ip9adhetgv2

I have used several of these. sometimes they are a bit stiff and can be filed down. Best price I have seen lately.

[pietro]

.

FWIW, it may be problematic to have a replacement spring shipped to Argentina.....................

You can do it, Argentino !


.

[Geezer in NH]

Note no location on his post saying Argentina

[John Boy]

Wondering if there is a method of getting it back to its original strength (like quenching it in oil and then tempering, or something like that).

Does anyone know how to do this? I can also try to make a new one, but I would prefer to fix and use the original instead. Your wasting your time - just buy a replacement ... http://www.rollingblockparts.com/