Percussion Cap Ignition Problem on a Colt 1860 Revolver

[Dead Slow]

I picked up a Uberti replica of a Colt 1860 revolver about 5 years ago. It was a disappointment and not very enjoyable to shoot. It would often take 2 or 3 hits from the hammer for the caps to ignite. Over the years I've tried different nipples, including Ampco and others trying to get a perfect fit. Nothing worked. I've tried wooden dowels, pushing with great force and with sweat pouring down my face trying to get those caps seated down as far down as possible. That helped more ignite on the first try, but sometimes half would still take a second strike before they would ignite. It was too frustrating to take this pistol the range much.

I got an old CVA copy of a Colt 1851 for comparison (I don't know who made it) and immediately noticed two things. It was much harder to cock the hammer and the caps ignite on the first strike. This pistol works.

I've explored the 1860 mainspring issue before to no avail as replacement parts were just duplicate failures, but now I had a working standard to compare to, so here is what I found:


On the left is the Uberti 1860 mainspring and on the right the CVA 1851. Notice the CVA is bend higher and it's also thicker at .056" compared to the Uberti at .046. It also looks like a much better quality piece of steel :




Here is the CVA 1851. Notice the spring sits right on the roller and that the hammer has a half circle cut just to the left:



On the Uberti 1860 the spring goes further in and the hammer lacks the nice half circle. I can't even swing the spring in and out like 1860 disassembly instructions show because it extends into the frame and blocks it (the picture does not show that very well) :



First I tried to install the CVA spring in the Uberti but it would not fit. Even though they appear to be the same length, the bend in the CVA spring prevents it from fitting in the Uberti.  Not wanting to mess with a good spring I next bent the Uberti spring in a vise to match the CVA. Then I had to loosen the trigger guard screws before I got it in. It was actually worse now because it scraped the inside of the frame and slowed down the hammer more. It was just too long now.


So next I ground down the end of the Uberti spring to get it to fit. This is what it finally looked like:




But even with the same shape as the CVA spring it lacked it's spring power, probably because it is thinner. It was still not reliable igniting caps.  So next I bent it back even further than the CVA spring.


For comparison, a new Uberti spring on the left and the extra bent and shortened Uberti spring on the right:



It's harder to cock the hammer now and the caps are igniting more reliably than before. I've only tried it twice and had 5 out of 6 and 6 out of 6 ignite, so this is hopeful, but what I think I really need is a heavier mainspring of better quality, more like what is on the 20 year old CVA pistol.

Are there any sources for a heavier main spring?   I really want to make this pistol reliable and enjoyable to shoot.

[Fox Creek Kid]

Chief, you´ll get far more hits on this in the Gunsmithing Forum or Darksider´s Den. 

[Pettifogger]

The Uberti 1860 Army is well made and can be made very reliable.  First, start with Treso nipples and Remington #10 caps.  Not stock nipples and CCI's or Tresos and some other brand.  Tresos and Remington 10's!  This combo alone eliminates most cap problems.  Diagnosing Colt open top problems is an art more than a science.  Without cocking the gun and looking at it as the cylinder rotates its hard to tell what the problem is.  Start with the Tresos and Reminton 10s.  Next make sure the relationship between the hammer and the nipple is correct.  This needs to be looked at with the cylinder all the way to the rear as well as all the way forward.  If the cylinder has to much end shake it's never going to be reliable.  Ideally, with the cylinder all the way to the rear the hammer should just kiss the nipple.  With the cylinder all the way to the rear the cylinder gap should be .006" to .008" (This is the end shake.)  The cap is around .006" thick.  This should make the hammer strike about perfect.  If the end shake/nipple clearance is wrong you will never get reliable ignition.  A weak mainspring (unless it is really weak) will usually set off the cap if it is seated properly and the end shake/nipple clearance is correct.  Where a weak spring shows problems is when the gun fires it won't seal the nipple and gases coming out of the nipple will blow off the cap and jam the gun.  If everything is correct and you need more spring strength, order a new one from VTI or you can cut a piece of spring off an old one and make a helper spring like in the photo.

[Dead Slow]

I just measured.

The cylinder gap is .018"

[Pettifogger]

It will never fire reliably with that big of a gap.  Period....

[Dead Slow]

I don't know why the gap is so large. The wedge is all the way in too and nowhere near binding the cylinder.

Today I went to the gunshow in Portland Oregon and searched out the old parts dealer. I asked about old Colt SAA revolver parts. He said he only had a few and pulled out an old box with assorted Colt Single Action Army parts. Among them I found a couple of old mainsprings.


For measurements, on the left is the Italian clone at 0.047", in the middle one of the old Colts at 0.071", and on the right the other old Colt at 0.085"


















The Colt 0.085" is a little long and would take some grinding down to fit in so next I tried the Colt 0.071".  It just barely fit in without modification.

It's harder to cock now and upon lightly slipping on 6 CCI #11 caps I went in the garage and all 6 fired on the first try. I'll try to get to the range tomorrow for a firing test.

[Dead Slow]

A local Cowboy shooter met me at the range today to check out the revolver. It turns out his  Remington #10 and #11 caps work perfectly, even with the original mainspring. CCI caps just don't agree with this 1860 unless an extra heavy mainspring is used.

[Pettifogger]

Well, Remington 10s were the first thing I said to try.  Now you need to figure out why your gap is so big and try to get it down around .006 to .008" for max reliability.

[Dead Slow]

Well, Remington 10s were the first thing I said to try.  Now you need to figure out why your gap is so big and try to get it down around .006 to .008" for max reliability.

The wedge is all the way in, so either it's too small or something else is off. I'll look at it in more detail later. It's been a long weekend. Are there any online sources for oversize wedges in case that's what it might need?

[Montana Slim]

A local Cowboy shooter met me at the range today to check out the revolver. It turns out his  Remington #10 and #11 caps work perfectly, even with the original mainspring. CCI caps just don't agree with this 1860 unless an extra heavy mainspring is used.

Hard for me to imagine BOTH Rem #10 AND #11s work.....if the 10s are working, the 11s should be falling off as you fire 
I have a number of Pietta & Uberti 1860s, all have factory cones....MY Uberti use CCI #10s, Pietta use CCI #11s..... no issues.

Size-wise, Remington #10s appear to be in-between CCI #10 and #11.

My Uberti 1860s factory mainsprings were borderline on giving reliable ignition. I did some creative bending to get a bit more "snap" out them. No issues popping CCI #10s on those pistolas.

Slim

[Dead Slow]

The Cowboy shooter had me load up and fire a full cylinder with the #11's to see if they would fall off and stopped me just before the last shot to check the last cap. It stayed on fine. The #10's went all the way to the end of the nipple smooth as silk. It was such a nice experience after struggling with the CCI caps.

Last night I ordered a thousand each of Remington #10 and #11's so I'm covered if anything else crops up, or falls off, later. 

[Montana Slim]

Boy, I'd like to get a look at them giant nipples that can take a #11 Remington 
(sorry, I just don't get a chance to say that often)

Have fun,
Slim