Weak main spring

[rpatmuck]

I have a weak percussion lock main spring.The rifle is a Ithaca Hawken that they made back in the 70's. It is not broken but age has weakened it to the point the hammer comes back every time you fire it. I put in new nipple and it still had the problem. The force to **** the rifle is half the force I have on other rifles I own. My question is how do I get this fixed? I am open to all ideas as I can not locate parts or replacement locks.

 

[FishDFly]

See if "The Log Cabin Shop" can repair or make you one.

 

[Old Hawkeye]

IIRC, the Ithaca is an Investarm made gun. My Investarm Hawken has the same hammer & other lock parts as the Lyman GPR. I'd call Track of the Wolf & talk their tech. They carry all kinds of replacement parts & I bet they have a mainspring that will fit.

 

[Larry (Omaha)]

I have a weak percussion lock main spring.The rifle is a Ithaca Hawken that they made back in the 70's. It is not broken but age has weakened it to the point the hammer comes back every time you fire it. I put in new nipple and it still had the problem. The force to **** the rifle is half the force I have on other rifles I own. My question is how do I get this fixed? I am open to all ideas as I can not locate parts or replacement locks.

Two solutions: 1. Replace the mainspring.
2. Anneal the spring, stretch it open a tad, then harden and temper. My guess is your spring was a tad too tempered (soft) and it eventually lost it's original shape. JMO

 

[rpatmuck]

See if "The Log Cabin Shop" can repair or make you one.

Thanks! I will call them on Monday!

 

[rpatmuck]

IIRC, the Ithaca is an Investarm made gun. My Investarm Hawken has the same hammer & other lock parts as the Lyman GPR. I'd call Track of the Wolf & talk their tech. They carry all kinds of replacement parts & I bet they have a mainspring that will fit.

Thanks for the advise! Monday I will call!

 

[rpatmuck]

Two solutions: 1. Replace the mainspring.
2. Anneal the spring, stretch it open a tad, then harden and temper. My guess is your spring was a tad too tempered (soft) and it eventually lost it's original shape. JMO

I would screw up trying to temper the spring. Replacement would be an option for me.

 

[Carbon 6]

2. Anneal the spring, stretch it open a tad, then harden and temper. My guess is your spring was a tad too tempered (soft) and it eventually lost it's original shape. JMO

I have always wondered if this was possible.

 

[LawrenceA]

I have always wondered if this was possible.

It is possible.
If you gwt it wrong the spring can be too hard and break or too soft and stay bent when compressed.

 

[Carbon 6]

It is possible.
If you gwt it wrong the spring can be too hard and break or too soft and stay bent when compressed.

Ya, I might as well go the extra mile and just make one from scratch. That way I don't screw up the original. Keep it for a pattern.

 

[Larry (Omaha)]

I would screw up trying to temper the spring. Replacement would be an option for me.

It is no good to you now! This is the best time to learn. You will be out nothing but your time.
Good luck.

 

[Grenadier1758]

I think that the Ithaca Hawken used the Cherry Corners lock. It was an Italian lock but used a traditional flat mainspring. Invest Arm locks have coil springs for their mainsprings. There may be a Pedersoli spring that will fit.

I built a Hawken using the Cherry Corners lock. I replaced mine with one of the mainsprings from the L&R Late English lock. I did have to drill a new hole in the lock plate for the locating tab.

 

[LawrenceA]

Ya, I might as well go the extra mile and just make one from scratch. That way I don't screw up the original. Keep it for a pattern.

Had to make one for a SxS a lot of years back from unknown steel.
Took4 goes

 

[Britsmoothy]

To harden the softened and reshaped spring. Heat to cherry red or a little hotter and drop in old engine oil....outside!
After that polish the steel shiny bright. You need to see the steel turn a plum colour as you heat it in an oven that can reach 400c+.

 

[griffiga]

Temporary fix, I had an original SxS shotgun and one mainspring was weak. I forced a couple strips of tin from a can in between the mainspring fold. Still works although I haven’t shot it a lot.

 

[Brent]

I am willing to bet that your nipple is a bigger problem than your mainspring. I would guess that you have been using it for a long time and it has burned out to the point that you are getting much more backflash than it should have. Try a new nipple.

That's not to say you don't need a new spring too, but always check your nipples and gauge their orifices with a drill bit shank and compare to a new nipple.

 

[FishDFly]

"I am willing to bet that your nipple is a bigger problem than your mainspring. I would guess that you have been using it for a long time and it has burned out to the point that you are getting much more backflash than it should have. Try a new nipple."

"I put in new nipple and it still had the problem."

 

[Britsmoothy]

Personally I'm not to worried about the hammers position after firing as long as your getting a reliable ignition.

 

[FishDFly]

Wondering, is there any damage that can be done, if the hammer comes back with too much gusto?

 

[sawyer04]

I would screw up trying to temper the spring. Replacement would be an option for me.

When you get the lock fixed with a replacement, do a little research and try to repair the spring. I bet you will be surprised what a common propane torch and a little oil can do.