PDA

View Full Version : Shimming the arbor...?


red96ta
January 28, 2013, 11:04 PM
I've read lots of things about shimming a Uberti arbor....but haven't found a reason for doing it.

I ended up shimming the arbor on my dragoon. The only difference I've noticed is that it's harder to remove the wedge....everything else is the same.

woodnbow
January 29, 2013, 09:32 AM
The idea is to produce repeatable cylinder gap everytime you assemble the piece... if left short you'll find that difficult unless you use a feeler gauge every time.

olmontanaboy
January 29, 2013, 09:59 AM
This article my help explain it: http://www.theopenrange.net/articles/Tuning_the_Uberti_Open_Top_Revolvers_Part_3.pdf

Willie Sutton
January 29, 2013, 10:03 AM
^^^ what he said.

You can not set up a Uberti to shoot repeatably accurately without having the correct arbor length.

Normal Uberti: Put the wedge in further and further and you bring the cylinder gap closer and closer and eventually it's rubbing. You are bending the barrel up and up and up... and the gun shoots higher and higher and higher. On many you can jam the cylinder to the BBL just using thumb pressure on the wedge. Tap with a brass hammer and you can definately jam them.

Fitted Uberti (like a Colt original is fitted): Wedge goes in to hold the frame and BBL together, and no matter how loose or tight you put the wedge in, the gap remains the same. Tap on it with a brass hammer... gap still stays the same.


This makes a huge difference in shootability, etc.


Willie

.

Noz
January 29, 2013, 02:21 PM
Willie's got it. Good job!

10851Man
January 29, 2013, 03:10 PM
Is it necessary to remove the wedge screw????

Idaho Spud
January 29, 2013, 04:29 PM
I never touch mine except I remove it when doing a complete cleaning as I do with all the screws. (I worry about rusty screw threads) Otherwise I just check to make sure it's tight enough to not fall out when shooting. That's just me, though.

Willie Sutton
January 29, 2013, 04:49 PM
^^ What he said.

You do not remove the screw to break the frame away from the barrel, and you do not use the screw to attempt to set the depth the wedge goes into the mortise. The ONLY reason AFAIK for the screw is to prevent loss of the wedge when disassembling for routine cleaning.


Willie

.

10851Man
January 29, 2013, 05:32 PM
Cool, I am new to open tops...Thanks

Roshi
January 29, 2013, 07:52 PM
Pietta seems to have responded to quality issues why can't Uberti?

Willie Sutton
January 29, 2013, 09:13 PM
^^ Heck of a question. Is there any way to get this info back to them? Thru Taylors, Cimmaron, etc?

It's not "quality" per-se, it's just one dimensioning decision that follows from model to model. It's not variable: It is obviously an engineering choice and not just an error, otherwise it would not hold true thru the entire product line.


Similarly, Pietta would increase their sales substantially if they lost the stupid markings on the barrel and put them under the loading lever like Uberti. I can fix an arbor, I cannot fix those damned markings. Can we get that word to them?


Willie

.

red96ta
January 29, 2013, 09:16 PM
Thanks guys, next question for you:

So now that the Dragoon is all shimmed up, the wedge is super-tight, as in so tight that it takes my rubber mallet to get it in and out. Is this a correct setting, or should something be ground in order to give the wedge a bit more room to breath and to be able to possibly get it to pop out with thumb pressure?

When I've got it together with the wedge out, the arbor hole and the hole in the barrel don't line up very well and this is causing the super-tight wedge fit.

Willie Sutton
January 29, 2013, 09:18 PM
Shoot it and it'll loosen up. They need to be shot-in to their final fit.

Go burn a pound of powder.


Willie

.

olmontanaboy
January 29, 2013, 09:51 PM
Similarly, Pietta would increase their sales substantially if they lost the stupid markings on the barrel and put them under the loading lever like Uberti. I can fix an arbor, I cannot fix those damned markings. Can we get that word to them?

Bingo, I agree 100%

Idaho Spud
January 29, 2013, 11:39 PM
I'm fairly new to this BP revolver thing and what turned me to the Pietta, and away from the Uberti was the arbor issue. Now that I know a bit more about these guns, I'd not let the arbor deter me from the Uberti guns. Looks like there're several ways to deal with it.

The writing on the Pietta doesn't bother me at all. My sole intent was to shoot mine. I'm not a Cowboy or anything, and I can understand those who collect disliking it, though.

Things sure are fun, though (except the clean-up)! I'm a bit paranoid about rust, so I completely disassemble every cleaning.