How to fix a '51 Navy cylinder rubbing on rear of barrel?

[Jubal Starbuck]

   I have a '51 Navy conversion that has too small a barrel/cylinder gap.  The bluing is being rubbed off the front of the cylinder by the rear of the barrel and it is harder to cock than normal, or  at least it seems that way.  What is to best way to correct this situation?

   Respectfully,

Jubal Starbuck

[Fox Creek Kid]

What is to best way to correct this situation?

Don't cock it. 

Seriously, either your wedge is driven too far into the arbor slot or it's just a poorly fitted example. Try backing out the wedge a tad. 

[Flint]

If it is a factory conversion, such as an Uberti made Richards-Mason, the wedge is the same as the Opentop.  It should be driven in until the retaining screw with its cutaway head can be turned into the cutout in the wedge (left side), then tapped back against the screw head from the right.  With the wedge cut face against the inside of the screw head, the wedge is properly located, and the cylinder should turn without binding.  If it doesn't, either the wedge is too wide, or the barrel throat extension is too long.

If it is a home made conversion of a cap & ball Navy with an R&D or a Kirst cylinder, the wedge will be a standard cap & ball type with the spring.  This wedge should be driven until the hook on the spring just hooks the barrel slot on the right side, and no further.  That location should not bind.  If it does, check the sqareness of the barrel throat extenson for parallelism to the cylinder face, and/or correct the cylinder gap as needed. 

[Major 2]

Is dragging all the way around or just in one spot on the cyl. ?

If the wedge is in to far it will bind and the fix is as Flint has suggested...
If on the other hand it dragging in just one area on the face and it the same place & the wedge is correct...

Then you have a high spot on the face of the Cyl .. I had a Walker with just that symptom and the wedge was correct..
the fix was to use a large flat Arkansas stone ( Grand dad was a butcher ) I just flat stropped the face until the bluing was removed
worked perfect !

[Coffinmaker]

Once you have followed the above the previous posts, and, if the cylinder is still dragging, you remove material from the rear of the barrel. 
There are two ways to do it.  Purchase a facing cutter from Brownells or set the barrel up in a padded vice and carefully make a few passes with a sharp bastard file then polish the face of the barrel.  Use an automotive type feeler gage to determine the barrel/cylinder gap.  It should be about .005,  +/- .001

Be careful with the file.  you need to keep the barrel face square.

Coffinmaker

[Jubal Starbuck]

    Thanks for your input, guys.  The cylinder front is shiny for about an eighth of an inch in all the way around.  The barrel wedge hook just catches the lip on the right side of the barrel.  Cylinder was fabricated by a local retired machinist.  I think i might try taking a small amount off the rear of the barrel, rebluing the cylinder face and try again.  I have some feeler gauges around here somewhere; I'll put them to use ,too.

Regards,

Jubal Starbuck

[will52100]

Sounds like a hight area on the cylinder or the barrel is pulled to far back on the arbor and making the rear of the barrel "pinch" the cylinder.  If the barrel/cylinder gap is triangle shaped, ie. widder at the bottom than the top then eigther the barrle is pulled too far back or the back of the barrle isn't square.  First, how hard is the wedge to seat?  If the wedge goes in easy but hangs up rite before seating the spring catch on the other side and you have to smack it very hard,  back it off just a tad and check your gap then.  If the gap remains wedge shaped, tighter at the top than bottom then eigther the rear of the barrel needs to be faced or the outer edge of the cylinder needs to be stonned.  Just remember, it's easy to remove metal, dang hard to put it back.  The barrel, arbor, and chamber should be in line.

I re-read your post, you didn't say where it was shiney, outside, middle, inside of cylinder?  I take it it doesn't have a gas ring?  If the barrel isn't being pulled too far back and isn't the problem take a fine stone and lightly stone the cylinder.  Watch your blueing to see if it is flat or if you've got a high spot.

[Jubal Starbuck]

will52100---The cylinder is shiny for abour an eighth of an inch in from the outside on the front end.  There is no gas ring on this revolver.  When the wedge is seated I can see a very narrow wedge shaped cyliinder gap, narrower at the top.  when wedge is just short of being seated, the gap appears to be more  even.  I put a square on the rear of the barrel and it is square, so I'm thinking the barrel is being pulled too far back at the top when the wedge is fully seated.

   Thanks for your input,

        Jubal

[Pettifogger]

I would almost bet this is a Uberti, they seem to have relatively poor barrel to arbor fit.  As an experiment, take the barrel off and remove the cylinder.  Put the barrel on at about 90 degress to the frame.  Rotate the barrel down to the frame.  Ideally, the barrel should just slide over the frame until it hits one of the alignment pins or be just a couple of thousands low.  On most Ubertis when you rotate the barrel, the barrel will hit well below the front edge of the frame.  When the barrel is this low, when you put in the wedge it tilts the top of the barrel inward.  One way to cure this is to drill and tap a hole in the front of the arbor and put a set screw in the hole.  Adjust it until the barrel just mates with the frame and loctite it in place.  Now when you put in the wedge, the barrel can't tip back.  Make sure the set screw does not extend into the wedge slot.

[Flint]

Pettifogger makes a point that has been a criticism of the Italian Colts from the beginning.  In order to make the fitting and finishing faster and cheaper, the arbor pins are made short.

Original Colt arbors were made long, and shortened by the assembler hand fitting the gun to a correct fit, contact of the arbor into the barrel lug a hair before the frame touched the barrel.  This makes the barrel parallel with the frame and cylinder no matter how hard you drive the wedge.

I have done as Pettifogger suggests on some of my guns, and it does make a more solid assembly, and prevents seizing the cylinder.  Another approach I have used is to make brass spacer washers on a lathe to fill the gap.  That requires precise measuring, and remembering the washer is in there upon disassembly, and which gun it fits.

[will52100]

Jubal, from your discription eigther your wedge is slightly oversize or the barrel needs to be shorter.  From what your describing your over pulling on the arbor and causing the barrel to tilt back and pinch the cylinder.  You want around .005 if I remember rite head space.  Test this with dummy rounds or fired cartriges, never live rounds!  The reason you test with dummy rounds is that sometimes the cartrige head will change the headspace.  The orginal conversions headspaced on the ratchet teeth and the R&D and Kirst headspace on a partition on eigther side of the cartrige.  I don't know how yours was made. From your discription I would probably very carefully file down the side of the wedge, it's pretty clear that to get the wedge seated as is your tilting the barrel back, that means its going over parallel and past where the barrel should be.  A lot of times when I've replaced wedges or barrels I've had to stone the wedges a little to get proper fit.  I would fit it so that the wedge spring just catches on the other side with a headspace of around .005.  That should get you where you want to go. I wouldn't take any off the barrel.

I have a Kirst conversion that I was attempting to mill a channel for an ejector and screwed up the barrel.  The new barrel I put on it wouldn't let me fully engage the wedge and was pinching like you discribe.  I couldn't even get the wedge started good before it pinched.  I fitted it by removing a little material from the rear of the barrel lug to set the whole thing back, then set the head space by grinding the rear of the barrel once I had the barrel moved back enough to fully engage the wedge and the barrel was parallel.  This was a uberti and the new barrel was grossly oversize in length and not the same problem I think that you have.  With your gun and the symtems you discribe removing material from the rear of the barrel would be my last choice.  If it's a pietta you won't be able to move the barrel back without removing material from the front of the arbor, and if the wedge slots are pretty close it won't do you any good to move the barrel back.

A side note, I had a conversion, and a cap gun, that I couldn't figure out why it was binding after only one or two shots.  Turned out that the arbor has  turned down area in front of the cylinder that keeps the area of contact between the cylinder and arbor out of line with the gas after firing.  The couple that I had jamming issues extened past the cylinder face a little and were directing flame into the cylinder/arbor interface, causing it to foul out fast.  I discovered it after a lot of test firing and noticed the flame cut on the arobor was on the edge and lower part of the arbor on guns that worked flawlessly.  On the guns with the jamming problem the flame cut was on the top of the thicker area of the arbor.  A little fileing with a needle file to bring the flame cut on out and the problem was solved.

Once you get everything set and running rite putting a screw in the end of the arbor to make it bottom is a good idea.  I've never felt it necissary to the point I was willing to spend the time to do it though.  But it would make getting the proper head space almost automatic.  I haven't though of the screw idea, I was thinking of welding or making a screw the same size as the arbor and making it look like the arbor was made that way.  A screw set in and sticking out of the end of the arbor a little would be a lot easier and untill broken down for cleaning one would never see or know about it.  I may give it a try.

One reason I would set the headspace with the wedge barely protruding through the other side is that any strech or wear can be taken out with the wedge provided you don't have a bottoming arbor, though most wear will be on the wedge and with it barely sticking past the outside you'll have a lot more wedge to wear on.  It will wear, but it'll take a long time.

[Jubal Starbuck]

    will52100---
  I carefully stoned the sides of the barrel wedge until it just hooks in the other side when you push the wedge through.  The barrel gap is now even at .500" and no more cylinder rubbing.  I think the problem is solved.
  Thanks for your input, everybody.

   Regards,

   Jubal Starbuck

[will52100]

Glad it solved your problem.  The colts are elegant guns, but for all modern tooling you can't replace hand fitting with CNC yet.

Have you test fired it yet?  That's the true test.