Uberti revolvers tuning

[lone pine]

I should have posted this earlier. been watching thread on short arbor ubertis. I have no mechanical or metallurgical knowledge like a lot of the posters here. when we took navy arms colt pistols out of the box in the 1970's we cleaned them out from factory grease and just shot them. I have ordered several books on tuning cap and ball revolvers. I am continuing to watch the info on short arbor ubertis.
lot of good stuff there. I just don't have the savvy to understand all the details of the posts yet. anyway I'm grateful for what's been posted.
thx to all

 

[bpalbee]

I should have posted this earlier. been watching thread on short arbor ubertis. I have no mechanical or metallurgical knowledge like a lot of the posters here. when we took navy arms colt pistols out of the box in the 1970's we cleaned them out from factory grease and just shot them. I have ordered several books on tuning cap and ball revolvers. I am continuing to watch the info on short arbor ubertis.
lot of good stuff there. I just don't have the savvy to understand all the details of the posts yet. anyway I'm grateful for what's been posted.
thx to all

The problem I noticed with the short arbors is they allow the barrel wedge to pull the forcing cone directly against the cylinder face when tapped into place, which is bad for reliability and can jam the weapon easily. It also allows the wedge to pivot the barrel upwards as it is tightened hurting accuracy. I have seen this on Ubertis, 2nd 3rd gen Colts, and Pietta I've handled even made in back in the 70s. More experienced people than myself have commented it's not so much and issue for casual shooters as it is for those who want to extract every bit of performance from their revolvers. Several people have mentioned from experience the original 1st generation Colts didn't suffer from short arbor syndrome. I believe this, Colt's gunsmiths finishing the arbor the proper length would be expected on a tool being relied upon in life or death scenarios.

 

[CaptainKirk]

Logistically it only makes sense to have the exact cylinder-to-forcing cone clearance every time you drive the wedge home, and also to have a solid 2-point mount (barrel to arbor and barrel to frame). If the arbor is resting solidly inside the arbor bore, the cylinder gap will never change. Think about it.

 

[Smokerr]

I can't get an image in my mind of the dynamics you quote, will leave that to 45D. I don't see a large amount of twisting being good for a Colt open top type pistol (well any pistol but the arbor system being a Colt open top specific design)

I believe this, Colt's gunsmiths finishing the arbor the proper length would be expected on a tool being relied upon in life or death scenarios.

That is kind of odd as not many use a Colt open top in life and death situation. Policy would be the ones who would the most and none of them (a bit of sarcasm) use an Open Top (well that I know of).

The originals while in theory life and death would have been framed (pun) in an era of knowing that nothing firing wise was as assured as a modern cartdige gun. Quality control of caps being one I can think of as well as cap jams, bad loading, bad powder you don't know about until you fire the gun etc.

I am curious about the original caps and how good quality/reliability wise they were.

 

[M. De Land]

Logistically it only makes sense to have the exact cylinder-to-forcing cone clearance every time you drive the wedge home, and also to have a solid 2-point mount (barrel to arbor and barrel to frame). If the arbor is resting solidly inside the arbor bore, the cylinder gap will never change. Think about it.

Well, that's good theory and in a perfect world more or less true but not in the real world and especially with brass frame guns and/or soft, ill fitting wedges with any model of open frame gun that can and often does change barrel cylinder gap width and level.

 

[45D]

Well, that's good theory and in a perfect world more or less true but not in the real world and especially with brass frame guns and/or soft, ill fitting wedges with any model of open frame gun that can and often does change barrel cylinder gap width and level.

But I will say, as long as the "fix" (a single spacer fitted how ever . . . ( shim stacks are never a good idea!!)) is a GOOD fix, the wedge should also be good for the duration. The arbor will stay the same length, the spacer will retain its thickness* so the endshake/gap will remain the same. The "real world" is quite attainable!

* what I've practiced over the years is, there needs to be a minimum thickness for the spacer (but i don't have a number!! ). In other words, it's a lot to ask for a "too thin" (barely there) spacer to be THE "connection" of the arbor to the barrel assy . . . therefore it is sometimes necessary to stop thinning the spacer and remove material from the end of the arbor ( YES!!! make the short arbor shorter!!!). That way you'll have substantial material ( arbor, barrel assy AND spacer ) for the fix rather than a possible / probable
"temporary" fix.
Some food for thought . .

Mike

 

[CyrusP]

That makes sense Mike. Too thin and damage can occur to the spacer. Therefore shorten the arbor to allow a thicker spacer. I finally understand something!

PS it’s still easier to send them to you.

 

[wiscoaster]

Mike Belliveau's (duelist1954) YouTube videos on tuning cap 'n ball revolvers are really excellent. This video is part one and if you go to his channel he's got more: