Italian mainspring types: Chiappa carbine .44-40

[Bullshooter!]

I commented on my other thread about the very heavy trigger pull and 3 click clunkiness of it. Probably between 15 and 20# pull guessing.
My other carbine the .45 Schofield has a much more manageable trigger, light by comparison though probably still 6 # or so.
I popped the lock off the .44-40 yesterday after reading a bit about this issue here and the myriad suggestions as to how to fix them, some I dont feel qualified to do like working on the mainspring itself by thinning, grinding, honing etc., but I was curious about other aspects, such as lubrication or lack thereof.
Sure enuf there was little to none in the lock works, so worked some grease into areas where parts move against one another, check screws for tightness and otherwise just looked around, then put it all back together. Amazing what a little lube will do.  The 3 click clunky is gone and while the trigger is still too heavy, its almost useable now. It shot pretty well for me yesterday with its horrendous pull, so this should make it easier.
I pulled the .45 cal one out today and popped its lock off, a bit more work that one, but no slivers. I noted that it appeared to have had one of the mods to the spring I read about, in that the lower part seemed to have been thinned considerably, and it of course has a much nicer pull. It too was pretty bereft of lube so worked some into its innards as well.
So I popped the lock off the .44-40 again, and dang it has the same thing on the spring, but 2-3 times the pull weight!
They both look like the pic below.
So what gives here?  Obviously there is more to the story than just the spring

[El Supremo]

Hello, Bullshooter:

With double-leaf mainsprings, some pull weight can be achieved if, at full cock, there is a gap between the opposite insides of the leaves.  If a gap, which should be so, then the sear leaf pressure can be reduced by fitting a lifting wedge or round collar on the mainspring screw.  The thickness of either must still allow the gap.  Test a shim of approx 75% of the gap between the bottom of the sear leaf and top of mainspring screw head.  Watch for it rubbing inside the inletting.  Test the change and if better, a collar setup might be less likely to slip out of place. 

Please let us know what you find.  Thanks.
El Supremo/Kevin Tinny

[Bullshooter!]

I may have a bigger problem than this that may require a trip to the Mothership.  Hammer is not hitting as it should and is peening its face. You can see its only making about 20 percent contact. As compared with my other one, no peening and at least double the contact area.
Hammer as seen from behind leans out a bit, where the other one leans in a bit for better alignment.

I was going to swap hammers to verify, but was unable to get the other one off its stem without getting serious and often bad things happen when serious gets involved.

[El Supremo]

Hello, Bullshooter:

Sorry to see that. Short summary:
Don't risk a voided Warranty by fussing with it, call and return to Warranty Center, which may need entire gun to resolve the alignment issue.

Hammer tip peening is widespread, but not extreme on original Spencer's. It is also often present inside the hammer tip cups of musket locks.

Your photo's show way more than usual with, as you noted, less contact. A combination of varying, sometimes less compatible hardnesses and heavy mainspring force contribute to peening and minute dimensional differences in parting lines cause the misalignment. Inspect the rear of the striker for any peening that might spread it and restrict movement.

With hammer tip alignment off, a simple TIG weld and dress-up is only part of the solution.  Hammers are fitted individually to tumblers and for alignment.  Original Spencer hammers are also unlikely to be a proper (swap) fit on another tumbler.

At full cock, hammers should be tight on the tumbler shaft with zero wiggle. Never over tighten an otherwise lightly snug hammer screw to remove wiggle because that rarely solves the parting lines issue, and can break off the screw shaft! If screw removal allows the hammer to be finger wiggled off, it's not fitted well enough to prevent subsequent loosening! 

If tight, hammer removal requires the tumbler's shaft/hammer stud to be pushed, not pried, through the hammer with protective shims placed between the lock plate and hammer. I push or gently tap using a straight sided punch that bottoms inside the hammer screw hole, but does not rub the threads. Your other hammer may not interchange.

Thanks for sharing, esp the photo's.
All the best,
El Supremo/Kevin Tinny

[Bullshooter!]

Yeah, I had no intention of messing with this. Going to contact them with photos by email and if no quick reply I will call them and hopefully get an RMA for return.
Bummer, but I have plenty of other things to shoot.

Thanks!!

[Bullshooter!]

I emailed Chiappa on Sunday and today first thing I had a reply requesting proof of purchase, which I emailed right back, half hour later I had an RMA for its return.

Will keep you posted on progress.