tip for open top precussion revolver shooters.

[johnson1942]

this tip can be for open top cartridge shooters also. i have 3 uberti open tops revolvers. they are the same as a precussion revolver in that they come apart the same way for take down and are converted from precussion revolvers.2 are 38 special and one is 45 long colt, or 44 prcussion in barrel size. i always noticed that the barrel cylinder gap is a little to tight. they shoot wonderful with blackhorn 209 powder but i always thought if i shot real black their may be a problem with the cylinder binding due to fouling from the black powder. last night i was looking at them closely with a light behind them and the gap appeared to be tighter on the bottom then the top. this ment the back of all three of the barrels was not cut straight to the bore. this morning i broke all three guns down and useing my flat face crowning cutter and the right pilot for each barrel i carefully shaved the back of each barrel untill the high spots were gone and the face of the back of the barrel was perfectly square to the bores of each barrel. i then polished this cut on each one with 600 then 1500 grit emery paper wrapped tight over a flat file. when i put the guns back together the barrel cylinder gap came out perfect. each one is about 7 to 8 thousands. im very happy with that. i can now see that the gap is even and it will most likely now be able to shoot black powder if i should do so. i have never seen a open top made by anybody but uberti so i cant comment on them. i would suggest to all those interested, to hold you gun with a light behind it and see if the gap is tighter on the top or bottom. if it is, then the rear of your barrel isnt cut perfectly square to the bore. all i shaved off was the excess to make it square to the bore and the gap become perfect. you would have thought they could have done this at the factory but all three of my uberti guns were off. if you dont have a crowing tool as i do you will have to use a honeing stone that if very flat. now i also have a 4th uberti in a 1875 remington and the gap is perfect from the factory.how ever when i took the cylinder out i noticed when the factory drilled the hole for the fireing pin to go through their was a burr their and that area of the gun was a little ruff. this could possible cause a cartridge to hang up in that area. i spent a couple hours with 220 emery paper wrapped tightly over a large flat file takeing off that bur and polishing that area. that metal in that area is very hard but i got the job done. it would be nice if factories would finish the guns as my uberti guns are well made but they come from the factory with burrs, loose screws and backs of barrels not cut square to the bore. i also put a after market main spring in the remington as it was very hard to cock with the factory spring. now all four guns cock perfectly and are tuned just right for me. now soon i will polish each cylinder with jewelers polish so the cases come out easier when fired and ejected. hope i have helped some one improve their open tops with this simple observation and tip.

[Omnivore]

First, I don't know of an Uberti open top that has the cylinder arbor butting hard against the front (the blind end) of the barrel's arbor bore, as they should. I would NOT advise doing anything to the barrel without first shimming the arbor so that it bottoms out hard inside the barrel to create a consistent cylinder gap as the wedge is tapped in hard.

Second; most of my percussion, black powder guns have been set for a cylinder gap of three to five thousandths. Black powder fouling on the face of the cylinder isn't really a factor. Much more of an issue is the fouling of the arbor itself, inside the front of the cylinder, and that can be managed effectively by using enough lube behind the bullet.

My most recent Uberti open top is a Colt Walker. That one required a "shim" (a waffer, really) of nearly a tenth of an inch thickness between the end of the cylinder arbor and the blind end of the arbor bore in the barrel. If you can pound in the wedge enough to bind the cylinder against the barrel, you must first cure this deficiency by lengthening the arbor. Don’t even think about any further mods until that’s done properly.

There's much more to the issue of proper barrel-to-frame fitting though. For example, the barrel should contact the frame’s “water table” somewhat before that arbor bottoms out in the barrel, and that contact should be square, with full coverage. If the barrel contacts the frame too much before the arbor bottoms out, or perhaps in your case before the barrel/cylinder gap reaches the point where it was before you did your alteration, then the barrel angles upward as a result, and could certainly, in that case, cause a wedge-shaped cylinder gap just as you described. The cure would be to refit the barrel to the frame and arbor first.

I suspect (though I wouldn't know without having inspected your gun beforehand) that what you should have done is first set the cylinder gap by properly shimming the arbor, and then check for the amount of "preload" (how much sooner the barrel hits the frame at the water table before the arbor bottoms out) and possibly mount up the barrel between centers on a lathe and face off the barrel's frame interface surface (where the two pin holes are located)

That barrel-to-frame fit is important to having a good shooter that will hold up over time to a lot of shooting, and also hold sight regulation. I've never seen or heard of an Uberti open top Colt that was set up properly from the factory. Pietta is now doing a bit better, but their issue is more often having too much cylinder gap and thus wanting the arbor shortened rather than shimmed.

Understand that these are relatively cheap guns, and so I am very impressed with what you get for the money, just don’t expect them to be all set up ideally right out of the box. Chances are they won't be.

Search for the series of articles entitled "Tuning the Pietta" (parts one, two, three, etc.) for a detailed explanation, with photos, of what I've been saying. It applies to the Ubertis also, because any open top Colt should be fit together a certain way.

Sorry Johnson1942, but the way it looks from here you probably got a bit ahead of yourself, and I do not recommend anyone attempt to do the same mods that you did without first understanding the basics of how these guns are supposed to be fit, and fitting them accordingly beforehand.

[johnson1942]

your the expert, if their is a way to delete what i wrote do it. how ever they work fine and shoot very very well. i did not take thousands off the rear of the barrel, i squared it off with the bore or the barrel. that is what a pilot did,alien the cutter. again their was no big cutting here. they shot very well before and they shoot very well now. they go together well and come apart very well. they are not ruined. i considered the washer but then i would still have the back of a barrel that wasnt faced off. the cylinder didnt move around to day, their isnt excessive gap and i will never share anything again as cast bullets is getting way way too argumentive no matter what anyone post. i see it every where here on cast bullets. i see that on other peoples post and didnt post this to be call a dumb a--------. take it off who ever does that. nothing but nays sayers on cast bollits any more every where. i dont get that else wheres on the internet. dont feel sorry,or say sorry, that is putting it over the top. as george bush said read my lips. not thousands, just squareing it up like it should have been done in the factory.im sure your the expert but i did get advice and a feeler gauge from a very good gunsmith before i did this this morning.take this post off please. im done here.

[bedbugbilly]

Uberti open tops are notorious for short cylinder pins. The cylinder gap is achieved by the amount that the wedge is in the cylinder pin. I've been shooting BP revolvers for over 50 years and started out on an original '51 Navy. Even an original can have the cylinder gap adjusted by the amount the wedge is in. I've seen many fellows over the years who feel that they need to "drive" the wedge in . . . sometimes with the use of a mallet or even a hammer. A correctly fitted wedge should be able to be put in and removed with thumb pressure.

I've owned many different brands of Colt clones over the years as well - Pietta, Uberti, ASM, Navy
Arms (made by others), etc. I can't think of one of them that the cylinder gap couldn't be adjusted by wedge pressure. If you put the wedge in really tight, you can bind the cylinder up with interference with the barrel - I've seen it done many times. As Omnivore points out, fouling isn't usually a problem with binding a cylinder up due to fouling build up on the face of the cylinder. Fouling of the cylinder pin will though and that's why it's necessary to lube it will.

Sometimes folks worry too much about cylinder gap. If you have your wedge adjusted correctly and you cylinder moves freely it's not that big of a deal. For the price of a Uberti or a Pietta, I think they do a pretty good job. If a person feels the need to "tune 'em up" then more power to them as we all like our revolvers to be how we like them. But, before I'd start taking material off the breech end of a barrel, I'd be looking at other things first. It's a little hard to put material back on once it's gone. I'm just curious as to how tight you have those wedges driven in Johnson? If you use a mallet to put them in, each time you do it they will never be in the same. Thumb pressure seating of a wedge is far more consistent each time IMHO. It gives a more consistent cylinder gap and let's face it, on any open top the barrel "could" be canted differently each time the revolver is reassembled - not like a Remington NMA or a modern revolver with a top strap which allows for no barrel movement up and down.

[johnson1942]

i never put my wedges in too tight and i glad you pointed that out to every one. thanks for that. i just wentt out and shot 30 more rounds through my two 38 specials each and hit the small gone every time except 3 times. they work wonderfully for ruined guns with problems. their is no way squareing up the face of the back of the barrel can hurt anything. i have made dozens of perfectly square muzzle crowns and the back of a revolver barrel should be the same. my cutters are razor sharp and very easy to shave very carefully with. when someone says sorry, that indicates im the village idiot and he has the keys to the kingdom. that i cannot accept from anyone. thanks for stepping in bedbugbilly and talking like a knowledgeable man with wisdom and experience. my son came home just now and put some rounds though each uberti with out missing the small gong once. they are still working.

[Omnivore]

I use the plastic butt of a stubby screwdriver to tap the wedge in. That's enough to keep in place during a shooting session. I've seen where people have to keep tapping the wedge in as they shoot, and that's because the arbor and barrel are floating rather than being held fast together at the end of the arbor. Here's an example (at around the six minute mark);
https://m.youtube.com/watch?v=J7Cx8qMHxxA
at first I figured he was getting caps falling into the hammer cutout on the frame, but apparently his wedge was moving out, letting the barrel come forward, in turn letting the cylinder come forward under pressure from the hand spring, and the hammer wasn't reaching the caps. If your wedge, which is soft steel, develops a divot in it at the right place, from the forward portion of the arbor slot, then it might stay put well enough without the proper arbor fit.

johnson; I didn't think I was being impolite or calling you names. As I saw it we were having a discussion on purely technical terms, hoping to increase the general level of understanding. I would hope that we could have some disagreements, or correct one another on technical matters, without anyone getting their feelings hurt. Preferably I'd get either of two responses; "Thank you, I'll look into those articles, and by the way here is how my barrel was fit to the frame and arbor before I started..." or, "No, I believe you are wrong on the following points, and here is why..."

So please; I am sorry if I was harsh in my response. Let us start again, so that hopefully we can understand these guns in the same way.

Also, I have it on good authority that at least some of the original Colts would bottom out the arbor inside the barrel, thus setting a consistent cylinder gap (and thus a consistent barrel-to-frame angle so as to maintain sight regulation). That leads to the matter of sight regulation, which, if you're going to refit one of these guns, probably should not be done until the very last because only then do you have a consistent barrel-to-frame angle.

[45 Dragoon]

Omnivore is correct here. There is no way to have the same revolver each time you assemble it if you can set the gap with the wedge. The fact is, without a correct arbor fit, the further in the wedge, the higher the barrel will point up. The arbor stopping the ability for the barrel to be driven back further is what determines the barrel /cyl. clearance . . . every single time. Also, you can't remove the clearances between the arbor and the arbor hole and impart sufficient "preload" for arbor contact with just thumb pressure. That's why Colts instructions tell you tap the wedge out/ tap the wedge in.
The wedge is to hold two assemblies together under load and nothing more. It is not a gap setter.


The original Colt open top revolvers did in fact have arbors that bottomed out in the barrel assy.


With an open top of Colts design, the larger the barrel/cyl clearance, the faster binding of the cylinder on the arbor. Therefore, the smallest clearance will be the cleanest. I set all bbl/cyl. clearances to .002"-.0025". With this setup, you can run all day with full charges without having to take it down for "cleaning". Why? Because everything goes out the barrel and very little out the clearance.
It has been proven time after time after time that this setup produces the longest shooting, cleanest open top revolvers.


So, the first thing that should be done before cutting any thing or even shooting an Uberti reproduction open top revolver(or any repro, even the 2nd/ 3rd gens) is to fix the short arbor problem.


Mike
www.goonsgunworks.com
Follow me on Instagram @ goonsgunworks

[Ballistics in Scotland]

I didn't see anything but constructive disagreement in the useful information Omnivore offered. The only original open top Colt I now have is a factory rimfire conversion of the Pocket Police - nickeled, unfortunately, since it is actually in fairly good condition, but partly-gone nickel looks more scabious than it really is. The metal at the rear of the cylinder is far thinner than I think was wise, and I suspect that cylinders were a consumable item, but mine is all original. I think it was medium-badly stored for a long time, but fired little if at all.

It fits exactly the way Omnivore describes, bottoming on the end of the axis pin, with a very narrow cylinder gap. You might even run into trouble with a modern revolver, which could be fired fast enough to cause expansion. The gap isn't any wider at the top than the bottom, but I can't see any harm if it had been. The important place to keep fouling away from is the axis pin, and if fouling did impede the front of the cylinder, there would be more leverage to overcome this at the top than at the bottom. I believe the same applied with a London Navy I owned a quarter of its life ago, which on serial numbers had a slight chance of having been down the valley with the Light Brigade. That one certainly went together very tightly with the wedge always finger-tight.

[45 Dragoon]

Again, if the arbor fitment is right, you can't get the barrel to cause cylinder binding. Of course, "finger or thumb tight" may seem good enough but, the instructions say to tap into, tap out for a reason.
If you can seat a wedge with thumb pressure, you're a better man than me! I've seen revolvers that are " fine with thumb pressure " but, if you Tap the wedge in, the cylinder locks. That's a problem.

Mike
www.goonsgunworks.com
Follow me on Instagram @ goonsgunworks

[ironhead7544]

With the Uberti open top cartridge revolver, 1871 model, you can adjust the arbor for a better fit.

Look up "Tuning the Uberti Open Top Revolvers by Larsen Pettifogger".

I have had two 1871 Uberti revolvers. One was so close that I left it alone and the other needed adjustment.

The 1871 is the best looking and handling Colt IMHO.

The 1871 and the Henry/1866 Winchester were the first pistol/rifle combo using the same cartridge, IIRC.

[45 Dragoon]

The "how to check for a short arbor" procedure is not a good method and will give folks a wrong "diagnosis ".
The easiest way is to drop a washer down the arbor hole and re-assemble . If you can reassemble, you got a short arbor!!

Mike
www.goonsgunworks.com
Follow me on Instagram @ goonsgunworks

[Omnivore]

Thanks, Ironhead, that's the series of articles I had in mind. I wish someone would teach Pettifogger the difference between the words "to" and "too".

He thinks somewhat differently than I, but he describes the issues well, he shows things very well and has some interesting ideas. Why the arbor button would need to have a stem on it with a corresponding hole drilled in the arbor, is not explained. My Ubertis have simple, cylindrical buttons placed down inside the barrel's arbor bore. Potayto, potahtoe, I guess, depending on the tools you have at your disposal. The stem on the button would make it easier to chuck up and make adjustments to the thickness as you go.

I think 45 Dragoon may have the better system. If I understand it correctly it allows for fitting the arbor-to-barrel, and the wedge insertion depth, independently of one another. In any case the Pettifogger articles do show in detail the common issues to be addressed.

johnson1942; you're on the right track as far as a possible adjustment of cylinder gap, but it would be considered after fitting the barrel-to-frame-to-arbor. First things first, is all. That's the main point I wanted to make.

[45 Dragoon]

Omnivore, thanks and yes, you got it right !!
My method of correcting the arbor is by "filling in " (with shims) the hole and to meet the existing arbor. Doing it that way allows me to use a threaded hole in the end of the arbor (which extends into the wedge slot or key way) for an adjustable bearing surface for the wedge to bear against. This in turn allows you to "custom fit" your wedge placement (further in/further out) according to your likes/holstering needs).
The open tops are the most "customizable " revolvers ever produced!!!

Mike
www.goonsgunworks.com
Follow me on Instagram @ goonsgunworks

[Ballistics in Scotland]

Omnivore, thanks and yes, you got right !!
My method of correcting the arbor is by "filling in " (with shims) the hole and to meet the existing arbor. Doing it that way allows me to use a threaded hole in the end of the arbor (which extends into the wedge slot or key way) for an adjustable bearing surface for the wedge to bear against. This in turn allows you to "custom fit" your wedge placement (further in/further out) according to your likes/holstering needs).
The open tops are the most "customizable " revolvers ever produced!!!

Mike
www.goonsgunworks.com (http://www.goonsgunworks.com)
Follow me on Instagram @ goonsgunworks

That sounds like an excellent procedure. I would indeed say shims rather than washers, for the scale of adjustment that would be needed. I still wonder why they didn't do it the same way as my Mariette or the Lefaucheux breech-loaders, in which the barrel unit is threaded onto a large-diameter axis pin. Now there is a case for facing off the rear of the barrel until the cylinder goes in.


176144

[45 Dragoon]

Wow! Not "privy" to that revolver at all!!

Thanks Ballistics!! It works rather well and so far, my customers seem to like it!
I know there's more than one way to "skin a cat" but this one I came up with myself after turning my Dragoons into cartridge guns. They work rather nicely and the procedure seems to do wonders for the cap guns.

Mike
www.goonsgunworks.com
Follow me on Instagram @ goonsgunworks

[Ballistics in Scotland]

The Belgians hadn't really got their mass-production into gear before the day of the cartridge revolver. The "Belgian bridge" (for the cylinder scene) copies of the Navy Colt are definitely ones to avoid, although I think I remember a slightly modified German one which was fine.