1860 Spencer won't fully cock

[Hypnogator]

I just purchased an original 1860 Spencer rifle, supposedly in working condition, from a reputable dealer.  I have three days to inspect it.  The rifle appears to be in good shape for a Civil War veteran, but the hammer won't go to full cock.  It will easily go to half-cock, but I can pull it only a little further back, and it stops, like it's hitting something solid.  I'm going to be carefully disassembling it tomorrow (I've done some gunsmithing) to see if I can find out what's wrong.

Is this a common malfunction?  If so, what is usually the cause?  Is there a quick and (hopefully) easy fix? 

The rifle will be used mostly as a static display, but I want to be able to shoot it in comparison with the 1860 Henry to determine relative rates of fire.

Appreciate any help y'all can give me!

Gary Griffiths

[DJ]

I bought one like that once--got a discount because it "didn't work."  There was some kind of gunk in the lock that was gumming up the works.  It was a pretty easy fix.  Your problem may be completely different, but it's worth checking out.

[Blair]

As DJ said, it may be a simple fix.
Take the lock out of the gun and work the hammer to see how things move with each other. Do this very slowly. It will help you see better what the problem might be.
I hope this helps.
My best,
Blair

[El Supremo]

Nice to see you, Blair:

And, as we've discussed:
BEFORE removing the lock, best to put the hammer at half-cock to avoid possibly chipping the inletting from a low sear tail.
All the best.
El Supremo/Kevin Tinny

[Hypnogator]

Thanks, guys!  Appreciate the help, especially El Supremo's advice on making sure the hammer is on half-cock before disassembly. 

It's probably something simple, but if anyone else has suggestions, would like to hear them.

Griff

[Hypnogator]

Got it Fixed!  Couldn't find any obvious broken or misaligned parts, so completely disassembled the tumbler, sear, etc, but again found no broken or worn parts.  Reassembled, and the hammer would release on pressing the sear.  Reinstalled onto the rifle, and the trigger released the hammer.  Horrendously heavy trigger-pull, but the trigger was frozen solid before. 

FWIW, I was expecting the hammer to be further back at full cock than it is, but now it releases properly.  In short, wouldn't work, so I took it apart and couldn't figure out what was wrong with it.  Then I reassembled it and it works fine.  I hate it when that happens.  Would be happy to post pictures of the guts, if anyone is interested, but I have yet to figure out how to post pictures.

Anyway, again, thanks.

Griff

[El Supremo]

Hello:

I have been told that original military Spencers were designed so the the sear and hammer notches "work against each other" to create at least an 8# martial trigger pull weight.  The minimum pull weight to avoid the sear falling into the half cock notch and doing damage is approx 4.5#.  Heavier pulls cause the trigger finger to exert sufficient rearward force to pull the sear clear as the tumbler rotates.

There is considerable variation in the temper of mainsprings. Over 15# pulls are not unusual.  I have many original Spencer mainsprings and some are WAY stiffer.  Cocking effort varies a lot.  The springs were tempered by eye and the perception of heating color during the process created the variation.

A simple trick that might help reduce pull weight is to put a 1/8" X 1/4" .010" thick shim of layered pop can wall material lengthwise BETWEEN the bottom of the mainspring screw head and the top of the lower leaf wedge.  This lifts the sear leaf tip of the mainspring. I have also substituted modern mainsprings from Shiloh Sharps with varying success.  They are less stiff for lower notch loading.

Be careful to use a thumbscrew mainspring vise, available from Track of The Wolf, NOT channel locks, to BARELY compress and HOLD the spring.  Over compression of the spring can ruin it.  If you bust one, let me know and I can send you one, but it could be stiffer than yours. 

Because the notches work against each other, pulling the trigger causes the sear tip to cam the hammer slightly rearward.  This means the hammer mainspring leaf stiffness still places significant loading pressure on the hammer notch even if the sear leaf is lifted a bit by the shim.

Please don't be tempted to stone the sear tip or hammer notch.  That is a job for a true Spencer pro, not a campfire gunsmith, and if goofed makes for a safety issue and eventually expensive parts replacement.  Lukewise, thinning the mainspring arms can weaken them and hammer fall becomes too low to ignite some primers.  Smiles.

El Supremo/Kevin Tinny

[Hypnogator]

Appreciate the advice, El Supremo!  I hadn't intended to mess with the spring at all.  I'm not trying to make a match rifle out of the old girl! 

Here are views of the rifle on the wall, a closeup of the action, fully cocked, and a closeup of the tumbler.  I can't see any damage, but I'm no expert. 

https://drive.google.com/file/d/1nJzxvJjWJGnQNs0oJu1UF01lrHOYPGv-/view?usp=sharing

https://drive.google.com/file/d/1nfty27UxcA_qETuCt0PQVXbV44uUv1wP/view?usp=sharing

https://drive.google.com/file/d/1T9JIEVB7BRKk7dhkj0YS-5HAg_o8Z4PH/view?usp=sharing

Again, appreciate y'all's expertise!

Griff

[Blair]

Griff,
It looks like your half cock notch is warn. damaged or otherwise broken. This will often indicate that the sear is also damaged. A photo of the lock assembled (with the sear in place) might be a great help?
You may also have found that you can't remove the front lock screw without placing the hammer at full cock.
I do this as a matter of fact (at least to half cock) with all my firearms when disassembling them. Keven was correct to suggest this option to you.
How were you able to remove the front lock screw without being able to put the hammer at full cock?
I also suspect you may have some Sharps parts in you lock, which is why I would like to see a photo of your lock internals.
My best,
Blair 

[Hypnogator]

Blair,

Here is the best photo I have of the assembled lock, with the hammer in full cock position:

https://drive.google.com/file/d/1XcIemz3mvp42gyFETJqEZiGekrqhCMWn/view?usp=sharing

and here is the best photo showing the tumbler and sear:

https://drive.google.com/file/d/1ryBSbp0yM5ktr72BjgIIPD-Ntey-Jq-T/view?usp=sharing

Everything looks OK to me, but based on my limited experience with other CW pieces and replicas, I think the hammer should be further back to be at "full cock."  Do you think this might be a Sharps tumbler and/or sear?  If so, do you know of a source for replacement parts?  Do you suppose a Cimarron replica sear and tumbler would fit properly?

Your expertise is VERY much appreciated! 

Griff

[El Supremo]

Hello, Hypnogator:

I just sent you a Private Message. Please review your emails and let me know you saw it. Thanks,
El Supremo/ Kevin Tinny

[El Supremo]

Hello, again, Hypnogator:

I emailed you photo's of undamaged sear and tumbler parts plus lock with them in place.
Regards.
El Supremo/Kevin Tinny

[Blair]

Griff,
Perhaps with the photos Kevin sent you, you will be able to see that your sear and tumbler have been modified and need to either be replaced or rebuilt.
Replacement parts are almost impossible to find. And if you can find them, they will be very expensive. The tumbler will be the hardest to find.
Rebuilding them will require someone that is a good tig welder, and that person will need to know what these parts should look like. Then it will be a matter of filing and fitting.
Please don't be put off by what I am suggesting here. I believe any Spencer Rifle is worth saving. Finging a complete lock maybe the easiest way to go, but that won't be cheap either.
My best,
Blair

[Hypnogator]

Blair,

Much appreciate your and Kevin's commentary.  I have ordered a new original sear from Dixie Gun Works, so will have to see how the parts fit and interplay once it arrives.  Unfortunately, none of the "usual suspects" have an original tumbler.  Kevin suggested an expert tig welder in Ohio that can hopefully restore the half-cock notch.  Will provide some decent quality macro photos when I fit the new sear and center-fire breach block.  Hopefully with a minimum of problems with either item.

Again, thanks!

Griff

[Blair]

Griff,

Please be very careful with the new sear when you install it that you don't cause damage to it by working the lock action under full spring tension? The tumbler you have now is a mess but can be fixed.
I am glad to see you wish to get a center fire block to get this Rifle up and running again.
My best,
Blair