1858 timing

[DaveP (UK)]

Hi! I haven't logged in here for an age, although I do read from time to time...
I have a Uberti 1858 which appears to have at least one problem with it's timing. I have tried to research this on the web but most of what could find was Colt specific and didnt seem to relate too directly to my problem.To be brief, the cylinder bolt pops up well before the cylinder has turned to the proper position and is starting to damage the edge of the cylinder cutout as the bolt rides over the edge. If I hold a thumb nail against a visible slot it appears that the cylinder surface needs to move another 3/16 before being properly aligned for a clean entry.
I've been having some difficulty in deciding where the cause lies. I'd better confess that I had to replace the hand not long after I bought it because the original hand spring snapped. I researched it as best I could. Tried to make the replacement a match for the original, and got it shooting. So you'll understand when I say that my first thought was that I had shortened the new hand too much. But then, the hand does actually rotate the cylinder enough to lock up, and when locked up the chamber is tolerably well aligned with the forcing cone - Viewed from the muzzle I can just make out the bright line of the chamber rim all the way round. In fact it's ever so slightly wider on the trailing edge but if this was the only imperfection I could find I would leave well enough alone!
With this in mind, I can't see that the hand is too short, so I'm now thinking that the problem is with the operation of the cylinder bolt itself. The trouble is that the gun wasnt doing this when I first took it out of the box, and I cant see that I have done anything that could cause it. Sure, I have stripped it down, and did do a little smoothing work on some parts, but I only removed roughness, I didnt try to polish or even remove machining marks, and I was certainly careful not to alter any cam profiles. Now it looks (to me at least) as if one of the cams on the hammer needs to be significantly extended.
It's not disastrous. The gun is shootable, but I can see things getting worse in the future, and in any case I'm one of those who cant see a problem without thinking about how to fix it. I don't think I can get any further with this one by just thinking about it and I'd appreciate any insights you have to offer.

Nearly forgot - when I start to cock the action the bolt does release the cylinder before the hand engages - I understand that's correct! That's something then...

 

[denster]

It sounds like your revolver is just fine. The bolt is not supposed to drop directly into the locking notch but prior to it. Having it drop right in causes two problems. When cocked fast the cylinder will over ride the bolt. Second after a little wear the bolt will start dropping on the very edge of the locking notch and peening it. You want it just as it is dropping before the notch. That will cause a little blue wear at that point but no damage.

 

[rcflint]

The hammer only has one cam, it operates the bolt. The other features are the half cock and full cock notces, don't touch them for this problem.

The bolt wing facing the hammer is a spring, and if it iooks as if it is squeezed toward the other outboard wing it has lost pressure against the hammer's cam. It should be at least parallel to the other, or opening a bit. However, too much spread will lean the hammer over toward the left at the top and rub the frame as it falls, particularly on a Pietta, as they have a loose hole to pivot screw fit. Try adjusting the spring tension of the cam riding wing carefully by prying it sideways with a screwdriver blade. Check the hammer's cam for wear.

 

[Jim K]

The best way to deal with the bolt marring the cylinder is not to change the timing, but to lighten the bolt spring. That can be done a couple of ways, but I prefer to just use a Dremel tool rotary drum to feather the spring. If that is done so the force required to push the bolt ball down is about the same as that in a modern S&W, the problem of gouging should go away. (The bluing may still be marked, but that is of no consequence.)

Jim

 

[DaveP (UK)]

After reading Denster's post I tried to revisit the page that left me with the idea that the bolt was supposed to drop straight into the cutout in an attempt to understand where I had gone wrong. Hadnt saved it and failed to find it, but I did find this:
http://www.cascity.com/forumhall/index.php?topic=31421.0
which broadly confirms that I dont really have a timing problem (phew!) and also explains why I have a faint ring around the cylinder... D'you know, I dont recall reading anything in the manufacturers instruction book about not dropping the hammer from half cock, No one told me and I haven't even seen this point mentioned on line before. Cross with myself? Dont start me off!
Returning to my original concern, I suppose ought to consider reducing the spring pressure on the bolt a little. I'm a litle bit anxious about that because I'm going to find it difficult to tell when to stop. Modern S&Ws in working order are a bit hard to come by in these parts, and replacement parts are only a little easier.

Jim: If I do decide to feather the spring would it be best to work on the face or an edge?

While I'm trying to drum up some courage and/or a spare spring I think I will polish the top of the bolt and work a tiny tiny radius on its edges - just enough to make them blunt rather than a potential scraper. The cylinder is permanently marked now, but its a long way from being too worn. Would that be enough to slow further wear right down?

 

[denster]

Don't be hard on yourself. You would be amazed at how many really expensive Colt SAA have a turn line from just such handling. It doesn't hurt to break the leading edge of the bolt a very tiny amount. This would be the edge on the left when viewed from the rear. The trailing edge doesn't contact the cylinder so leave it alone.

 

[BHP FAN]

very good advice. you can tell denster knows his way around the inside of a Remmie, though the advice is good for Colt's as well. This is in fact why Colt's revolvers have that little ''half moon'' cut out on the leading edge of the cylinder stop or ''bolt'' notch in the cylinder.. knowledge of the proper use of the half cock is essential for handling any single action revolver.