Uberti 1862 Police .36 Hammer Blow Back

[Chowmif16]

I have a Uberti 1862 .36 Police model that is great to shoot, but has an issue.
The cap/hammer quite often blows back after a shot. So, the hammer ends up partway between fully seated on the nipple and half-cock. The cap then ends up off of the nipple and usually lodges between the cylinder and the channel for the hammer in the recoil shield. This then prevents cycling to the next chamber because the cap gets in the way.
I think it must be a result of one of or a combination of two problems:
Could be that the mainspring is weak and there is not enough pressure on the hammer resting on the cap/nipple to prevent this.
Could be that the stock nipples are a contributing factor with too large a diameter flash-hole which allows the back pressure to push the hammer back.
It seems to happen with very light loads, down to about 10-12gr FFFg. The cylinder will certainly hold more along with the .375 ball.
I wonder if some Treso nipples with the smaller flash-hole diameter will help, or do I need to shim the mainspring to make it stronger?
I've got about 10 cap n ball revolvers and none others do this.
Anyone here run into the same problem with this particular gun?

 

[DOUBLEDEUCE 1]

I bought two 1862 Uberti Pocket Police revolvers. I replaced the stock nipples with Treso brand nipples on one revolver. I left the other with the stock nipples. Both were fired with the same charge. I didn't experience any problems with blow back on either revolver. I don't know why, but I like the Treso nipples better than the stock ones. :idunno:

They are fun to shoot! :thumbsup:

 

[thecapgunkid]

Chow...

If it's doing this out of box then it is not so great to shoot. Probably need the vendor ( if someone like Taylors) or Uberti ( maybe via e-mail first)for some help.

For example...does it do it on all cylinders? Does it index well every time you cock it? Can you see whether the mainspring is seated right on the base of the hammer? Any internal wear signs between spring and frame you can't see while it is assembled?

I'd be a little reluctant to shoot it until you get it settled, because problems like this don't get better by themselves.

Nice P-47, by the way....

 

[hawkeye2]

"the hammer ends up partway between fully seated on the nipple and half-cock"

Is the hammer remaining back in this position or does it fall back on the nipple? If it sticks back there off the nipple the gun has some serious problems. If it is blown back and returns down on the nipple you have two possible issues. The first and most obvious is the nipples. The factory ones need to be replaced with Treso nipples. Some claim this will solve the issue but my experience is that it only helps and and doesn't cure. They do provide more consistent ignition as the flash holes are all of the same (smaller) size and in the center of the nipple. Your second issue, and it's possible you have a combination of the two, could be a mainspring that is too weak. I have a Uberti '62 pocket police that I had never fired but the mainspring always felt far too weak. I sent it off to a Cap and Ball specialist for a complete tune up and a cap post mod but haven't got it back yet. You might be able to shim the mainspring but remember that will move it back by the amount of the shim and sometimes the spring is a little too short and it's possible it could move it enough that the hammer will slip off the end as you cock it. Even with Treso nipples and a good mainspring I have never found a Colt style to be free enough from cap jams that I would consider using one in N-SSA revolver team matches or CAS without further modification.

 

[Chowmif16]

Thanks all for the replies, and I will clarify that the gun indexes well and otherwise functions perfectly.
Hawkeye, good question about the hammer staying back. I didn't give a great description of it. The hammer ends up staying back because the cap inevitably comes all or part way off the nipple and then gets in the way of the hammer from fully returning/seating on the nipple. So, it is not a problem with the action of the hammer from what I can tell.
I will try the Treso nipples. I also think the mainspring is weak like you mentioned on yours.
Cheers,
Chowmi

 

[ccmountainman]

Do you remember the Treso part # for these nipples?
Might have to get some myself.

 

[Crow Beads]

Check to see if the hammer is rubbing against the grip frame. I've seen this in more than one of my Ubertis. That may account for the weak hammer strike. The stock springs are more than adequate for ignition.

 

[AZbpBurner]

Do you remember the Treso part # for these nipples?
Might have to get some myself.

Treso #11-50-30
5.5 X 9mm
The packages are marked: ".31 Remington Pocket Revolver", but also fit the Colt. I installed a set, since the factory nipples were a little shorter and, combined with the cylinder play, the hammer wouldn't reach to reliably fire a cap.

 

[Chowmif16]

I installed Treso nipples, and it has solved my problem.
Very happy about that!

 

[DOUBLEDEUCE 1]

Good to know. :thumbsup: