Double checking the arbor end fit on my 2022 Pietta 51

[M. De Land]

I had some shop work earlier today and after finishing decided to re-check the arbor end fit on the Pietta 51 I picked up from Cabella's last year not being satisfied with my earlier check fit I made on the gun. It's stamped on the bottom barrel flat IT2022. I've been hearing the new Pietta's have been showing up with proper arbor fit so thought I better give her another look and apparently it's true.
My new Walker (Uberti) on the other hand required a substantial plug of steel to fit the arbor end properly !
The Pietta 51 fit perfectly from the factory once I got the well bottom good and clean and tried first a .015 shim then down to a .010 then a .005 and finally a .0025. Each thinner shim showed a decreasing gap of light on the lower lug fit up to the frame while on the pins with the cylinder removed and bumped together with a rawhide hammer.
I installed the thinnest .0025 shim , put the cylinder on, drove in the wedge and barrel gap was .005-6 with light showing in the lower lug gap. Removed the wedge and .0025 shim, put the cylinder back on, drove in the wedge and the lower lug light gap closed , checked the barrel /cylinder gap and it feeler gauged .0025-3.
I completely agree that removing the cylinder and swinging the barrel assembly if it will (some won't swing) to see how it lines up with the frame lug seat isn't very accurate and that because of arbor radial clearance that lets the barrel assembly tip but when you remove the cylinder, put the barrel assembly on the lug pins over the arbor it's whole new kettle of fish in determining how much end play is present.
You can hold the lug up to a good light and watch it close up as the shim on the end gets thinner. When it closes up with the wedge driven in your there. You can see this within .001 or less.
So this 2022 Pietta 51 did come from the factory properly end fit. Good for Pietta now if we can get Uberti to get their ducks in a row !

 

[Phil Coffins]

Good technique to determine arbor fit!

 

[earlwb]

I would try pulling the wedge and any screws holding the barrel on, then heat the barrel around the arbor to expand it slightly, then try using the reload press bar to see if it might come loose then. Or use the brass or wood dowel down the barrel to wack it loose with a wood or leather mallet. I think that the metal around the lip of the arbor just might have a lip on it. But you won’t know until you get the barrel off.