Correcting Uberti Short Arbors?

denster said:

All of this work and you can't spend five minutes correcting the arbor length. I guess I just don't understand the feeler gauge fetish and the desire for a flexible firer????

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You have to get over the notion of making an open frame gun rigid like a solid frame gun because it never will be regardless if the arbor fills up the arbor well or not. The filled up (solid) arbor well does nothing for accuracy under the forward pressure load at firing as all the load is on the slots , wedge and lower lug not the end of the arbor. Open frame guns are designed with flex in mind. The trick is to get them to do the same thing every time and this happens with equal pressure load on both sides of the barrel in the slots, arbor slot and lower lug fit. The gun just doesn't care if there is some room at the end of the arbor and arbor well.
I'm reasonably sure that is why Uberti and early Pietta's did not go to the trouble to address this and yet Uberti went to a lot of trouble in the rest of the guns fit and finish early on and now Pietta is following suit.
Customers get ideas in there heads and demand change wither it makes any sense or not and so gun makers usually comply sooner or later.
I have no trouble fitting the arbor well but know from experience it just isn't that important to accuracy compared to other considerations.

M. De Land said:

You have to get over the notion of making an open frame gun rigid like a solid frame gun because it never will be regardless if the arbor fills up the arbor well or not. The filled up (solid) arbor well does nothing for accuracy under the forward pressure load at firing as all the load is on the slots , wedge and lower lug not the end of the arbor. Open frame guns are designed with flex in mind. The trick is to get them to do the same thing every time and this happens with equal pressure load on both sides of the barrel in the slots, arbor slot and lower lug fit. The gun just doesn't care if there is some room at the end of the arbor and arbor well.
I'm reasonably sure that is why Uberti and early Pietta's did not go to the trouble to address this and yet Uberti went to a lot of trouble in the rest of the guns fit and finish early on and now Pietta is following suit.
Customers get ideas in there heads and demand change wither it makes any sense or not and so gun makers usually comply sooner or later.
I have no trouble fitting the arbor well but know from experience it just isn't that important to accuracy compared to other considerations.

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I don't think I will get over it. Nor will many who use these guns hard in competition. You are just as free though to think that I am wrong and continue with your flexible firers.

denster said:

I don't think I will get over it. Nor will many who use these guns hard in competition. You are just as free though to think that I am wrong and continue with your flexible firers.

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Ain't America great?
You are free to think as you like but it won't change the design character of open frame guns. If they are set up right I believe my 60 is fully the accuracy equal of my match 58 which is a better than my ROA. It's just that they don't have the sighting capability advantage that is present on solid frame guns that allows them to take advanage of the accuracy potential.

M. De Land said:

Ain't America great?
You are free to think as you like but it won't change the design character of open frame guns. If they are set up right I believe my 60 is fully the accuracy equal of my match 58 which is a better than my ROA. It's just that they don't have the sighting capability advantage that is present on solid frame guns that allows them to take advanage of the accuracy potential.

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My recently found new-in-box Pietta Colt 1960 was mfg. 2017. I've heard they use CNC machinery nowadays, and I can believe it as it's really smooth and precise-fit! Beautiful finish, etc.

denster said:

I don't think I will get over it. Nor will many who use these guns hard in competition. You are just as free though to think that I am wrong and continue with your flexible firers.

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All open frame guns flex more than solid frame guns wither or not the arbor well is filled.

I have an Uberti 1860 Army made in 2019 that is the worst when it comes to short arbors: the gun would not wedge up at all until I glued in a shim. Over time the shim has 'broken in' and the gun still gets loose.

Well, today I just got another Uberti 1860, this time a 3-screw civilian model with its own set of problems. The boat from Italy must have sprung a leak because this is the second Uberti that I have gotten this month that had noticeable rust in it. This new 1860 civilian (proof year 2021) has a longer arbor than the previous gun. How do I know? Because the rusted nipples were so bad that I pulled off a Tuco shop fix by swapping cylinders and barrel assemblies, mating the 2019's front pieces to the 2021's frame. Whereas the wedge on the 2019 frame slipped all the way in with zero resistance, that same barrel/cylinder locks tight into the 2021 frame before the spring tab can barely make its way through the right side of the slot.

Hopefully this is an indication that Uberti has finally wised up and corrected the arbor length on their newest examples.

M. De Land said:

In my opinion it is a solution in search of a problem which is why Uberti did or does not correct it. Why would they go to the trouble of fitting the rest of the guns so well and leave the well long if it is a real issue?
First off in the button fix the guy purposely weakens the end of the arbor by drilling into the wedge slot for the button stem. Same deal when it is threaded for an adjustable screw. Second he filed the wedge to fit the slot better after inserting the button which should be hard and would make it difficult if not impossible to file.
The slots in the barrel and end of the arbor need to be fit to a properly shaped and hardened wedge not the other way around!

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i agree its not an issue for folks who dont have to fool with everything they own.

1861 Springfield said:

i agree its not an issue for folks who dont have to fool with everything they own.

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But, for folks that want whats "close" to be "correct", there are things you can do . . .

Mike

I have gone over this many times in previous posts but it’s worth explaining here again for all to see.

Uberti builds guns to a price point. One of their shortcomings is that the arbor does not bottom out in the barrel lug as Colt originally designed. This means that the wedge is holding the barrel away from the cylinder, which shouldn’t be the case. As these interference fit parts wear, if tolerances stack up incorrectly in the revolver or if the gun is repeatedly over wedged then the barrel cams upward/inward from the contact area at the lower frame. This gun exhibits those issues. This is a fairly common fix in my shop and as such is reasonably priced. I call it “arbor correction”. It not only fixes these issues but it also strengthens the gun and makes it more accurate as the sight alignment doesn’t change every time your disassemble/reassemble the revolver.

I agree. I shimmed a couple of Uberti’s arbors with washers and they now shoot point of aim after I reassemble them. I have some Piettas that have perfect arbor lengths, and in the future will probably buy more because of this.

I use tin foil to make a metal plug , to "shim" my arbor holes

It's worked so far and I shoot alot.

55 grain charges through my Walkers, many 100s of them . Not a single problem. Both arbor holes filled with tin foil .

No second place said:

Went to Dixie G.W. in 2019 to hand select a few Colts and Remmys to possibly use in NMLRA/ NRA matches in the 6+ hours I was there I examined (bore lights, Mag. glass, cleaning, Dial calipers) over 25 guns 51s,61s,60s and 62 Police (Uberti). Both Uberti and Pietta quality was far better than typical than expected. Prices were similar enough then. Pietta bore and cylinder were all better than Uberti. All the Pietta actions needed less tuning to be match ready. Only new 2019 purchase used in matches was the Pietta 1860 Colt (after tuning). Results were H.M gold Spring 2019 NRA sponsored NMLRA Nationals (four targets 25 and 50 yards). New Pietta 2019 .44 1858 is an amazing low cost match pistol after light tuning. First practice target after sight in at 50 yards beat my/the Nmlra National current record by 2 Xs. Ordered extra cylinders for that 1859 Pietta .Now have 5 percussion cylinders and a unmentionable conversion. All drop in fit, same dimensions says my dial caliper. Pleased with new Pietta quality control.I do agree though that for a display item Uberti are better overall...c

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Amazing they let you do that!!

Stantheman86 said:

I use tin foil to make a metal plug , to "shim" my arbor holes

It's worked so far and I shoot alot.

55 grain charges through my Walkers, many 100s of them . Not a single problem. Both arbor holes filled with tin foil .

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The lazy guy in me just wants to measure the barrel/frame overlap. Add a slightly larger blob of weld on the end of the arbor, and then file it down by hand until barrel gap is exact. Add more weld as necessary. It will be steel on steel and as good as an honest to goodness Colt at that point (don't say that on the Colt forum, they'll eviscerate you)

springfield art said:

Amazing they let you do that!!

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Have been told by other National competitors that's how you buy a new match gun. I would still rather buy from fellow competitors ...nsp

bpalbee said:

The lazy guy in me just wants to measure the barrel/frame overlap. Add a slightly larger blob of weld on the end of the arbor, and then file it down by hand until barrel gap is exact. Add more weld as necessary. It will be steel on steel and as good as an honest to goodness Colt at that point (don't say that on the Colt forum, they'll eviscerate you)

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The problem with that is facilitating the "overlap". The open-top typically won't go fully together unless the assemblies are correctly aligned. If you "dress" the arbor down to be able to do the "overlap", you just introduced even more slop in the fitment . . . The easiest/fastest way I've found is with fitting a single spacer. When you get the "endshake" you want, you're done. 10 -15 min start to finish.
If you want, you can mount it in the arbor hole leaving the arbor end free to install an adjustable wedge bearing. That allows you to adjust the wedge position if you have need to and of course adjust for any wear.

Always good to have options.

Mike

45D said:

The problem with that is facilitating the "overlap". The open-top typically won't go fully together unless the assemblies are correctly aligned. If you "dress" the arbor down to be able to do the "overlap", you just introduced even more slop in the fitment . . . The easiest/fastest way I've found is with fitting a single spacer. When you get the "endshake" you want, you're done. 10 -15 min start to finish.
If you want, you can mount it in the arbor hole leaving the arbor end free to install an adjustable wedge bearing. That allows you to adjust the wedge position if you have need to and of course adjust for any wear.

Always good to have options.

Mike

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I think I get what you're saying Mike, some of the Ubertis have a sight taper to the arbor, maybe part of their "adjustable" wedge scheme?. Yes, dressing down the diameter of the arbor would counterproductive to a stable/repeatable barrel attachment, we're trying to make the thing lock down tight end to end and side to side. I think the tapered arbor is why some of the Ubertis are so difficult to take apart when new.

Hmmm...maybe the FACTORY can help cure "short arbors"! Right from the get-go. Just sayin'. Good that guys here know how to tweak things, though.

Gun Tramp said:

I don't buy the "short arbor" theory, never will. For those that do, please study the drawing on page 62 of A History of the Colt Revolver. The "issue" bemoaned by Uberti owners is due to the relationship of the key (wedge) and arbor.

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Regardless of the cause of the problem, the washer shims seem to be the short and easy fix.

I don't think I will get over it. Nor will many who use these guns hard in competition. You are just as free though to think that I am wrong and continue with your flexible firers.

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Should not not be Flexible Flyers?

Regardless of the cause of the problem, the washer shims seem to be the short and easy fix.

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Sort of, from my experience and 45D knowledge base, its not solid, zero change. I see shifting POI for the POA as well as accuracy changes with the same loads. I just have not made the decision to take the time out and do it right.

I believe I am stating it correctly, if you are going into the areas of pressure he is exploring, then you will beat the gun up as well. I think I am safe with the low pressures I am shooting at, I could be wrong.

All open frame guns flex more than solid frame guns wither or not the arbor well is filled.

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The wing on a 787 (composite) flexes more than an aluminum aircraft wing.

So now you are breaking it down into degrees of flex for one is better than the other.

For those who do not get deep into this, a 1 inch Steel Barrel flexes on firing. Its less than a Pencil barrel, it does flex. Some Pencil barrels will shoot as accurately as a 1 inch.

45D does not just do well filled Arbors, he does solid lock up arbors.

There is a difference between flex and movement because of gap.

And the so called less flex of a top strap vs a open top is an opinion. No one has done the high speed pictures and measured the flex.

The assumption by Mr. De Land is an opinion, not a fact. He lives and breathes opinions by himself and others and then states them as facts. Its bad tech and science.

Harks back to Throwing a perfecly good maiden in a volcano and then saying, yep, that is why it stopped eruptio0n.

Thousands of perfectly good maidens (being somewhat biased I say throw the accuser in and the perfecly good maidens can have a nice life) and the accuser is still heck bent on throwing Maidens into the Volcano scream, but it will work this time (as the Lava finally pops at the right time, pours over his head and good riddance)