got my new Cimarron RM conversions, going to have to tinker with them

[Barrelhouse Bob]

Got  a new pair of RM conversions in  38 cal. Loaded up 100 rounds of 38 long Colt today with 777, and 50 with Holy Black. going to test fire tommorrow, can hardly wait for daylight.

If all goes well I'll shoot them at a match this Sunday.  YEE Haw !!!    

[Major 2]

welcome to the fold 

[Barrelhouse Bob]

Well I will not be shooting my new conversions at the match this Sunday. Got a little work to do before they are match ready. The barrel cylinder gap is too tight. With black powder or 777, they start to bind on the first cylinder. I  placed a 5mm lock washer between the barrel and the cylinder shaft, and just have the wedge in far enough to be flush on the far side, and the gap is still too tight. It would work just fine for smokeless, I believe.

[Fox Creek Kid]

Well I will not be shooting my new conversions at the match this Sunday. Got a little work to do before they are match ready. The barrel cylinder gap is too tight. With black powder or 777, they start to bind on the first cylinder. I  placed a 5mm lock washer between the barrel and the cylinder shaft, and just have the wedge in far enough to be flush on the far side, and the gap is still too tight. It would work just fine for smokeless, I believe.

Here we go again. The problem is not the gap. It's the lube. You need bullets lubed specifically for BP and LOTS of lube on the cylinder pin. LOTS.  

[Mako]

Bob,
Measure that cylinder gap and report the dimension to us.  Use a flat feeler gauges if you have them.  If you don't have a set, use plain paper. One sheet of plain copy/printer usually equals about .0033-.0035".

With your RM start with the hammer down and have someone hold the pistol for you; or take the wooden portion of the grips off and reattach the metal portion of the grip frame then clamp it carefully by the grip frame in a padded vise. Hold the barrel up slightly and holding first one sheet of paper stretched between your hands fit it between the cylinder and barrel. After you try one then take two thicknesses.  Do not measure at a fold, it needs to be two free edges.  If two fit try three.

You want two thicknesses to fit.  Let us know what you measure with a feeler gauge in inches or how many sheets of paper fit.  We'll walk you through this.

Regards,
Mako

[Barrelhouse Bob]

With the hammer down, I can not get a feeler gauge between the cylinder an barrel. If I put the hammer on half cock, and hold the cylinder back. I can get a .002 feeler in but not a .003.

Also the barrel and cylinder are not square to each other. The cylinder rubs against the barrel in one spot, and clears the rest of the rotation.

[Fox Creek Kid]

...Also the barrel and cylinder are not square to each other. The cylinder rubs against the barrel in one spot, and clears the rest of the rotation.

How are you inserting the wedge? Does your conversion have the "dish out" in the wedge for the screw? If so, just drive the wedge in UNTIL the screw will just turn into the "dish out" & no farther. Then try & cycle it. Remember, you need to grease the cylinder pin LIBERALLY.

[Mako]

With the hammer down, I can not get a feeler gauge between the cylinder an barrel. If I put the hammer on half cock, and hold the cylinder back. I can get a .002 feeler in but not a .003.

Also the barrel and cylinder are not square to each other. The cylinder rubs against the barrel in one spot, and clears the rest of the rotation.

Bob,
First of all it concerns me that you have more clearance with the gun at half cock than with the hammer down.  There isn't anything for the hammer to push forward on a Richards Mason Conversion cylinder.  I fact at half cock you will have a very small amount of hand pressure forward.  Hammer down on a cartridge pistol is the least amount of forward pressure.

Now, on a cap and ball revolver it is the opposite. The hammer pushes forward on the cones on a C&B revolver. Hammer back to measure C&Bs,  hammer down on your cartridge guns.  If this is not the case with your pistols then post again, because you have a situation that we will need to figure out before moving on.

You want your cylinder gap to be .006" - .008" on your Black Powder cartridge conversions.  Some people may disagree on the gap, but I will guarantee you it works and doesn't readily foul out if you are using correctly lubed bullets and grease on your arbor.

The Fox Creek Kid definitely had the right course of action for your next corrective action.  I would ask the same question about the wedge retaining screw.  I'm pretty sure all of the current Uberti conversions have the wedge with the screw blocking cut out instead of the wedge retention spring the C&B pistols have.  If it has this feature do what the Kid said, here is a point by point way of trying to increase your cylinder gap.

• After replacing the barrel tap your wedge in until you see the clearance slot on the wedge just pass the edge of the barrel.
• Turn the screw down, the edge should now be blocking the wedge.
• Tap the wedge back very lightly to just touch the screw.  (this is the minimum engagement possible with your screw fully tightened)
• Check your gap.  If it is less than two sheets of paper or .006" then you will need to move the wedge out.
• Moving it out a controlled distance is the easiest change at this point.  You back the wedge screw out a complete revolution, the screw's pitch is .028 per inch so the screw will move out that much.  Now tap your wedge back to the screw and remeasure.
• Remeasure, and it should be at least .001" greater than it was before.  The wedge taper is only about 2°15' overall.  So you can turn your screw out however many full revolutions you need (at a gain of .001" per turn) to get your gap of .006-.008".

The reason your gap may be pie shaped may be the wedge insertion depth.  If the wedge is in too far it will be pulling the barrel back which often gives you that non parallel gap.

Before you do anything to try and square that gap you have some work and exploration to do.  Don't touch that barrel end with any tool until you get your other issues like the arbor to arbor hole fit totally resolved.

I have a question about your wedge insertion from your earlier post:

...I  placed a 5mm lock washer between the barrel and the cylinder shaft, and just have the wedge in far enough to be flush on the far side, and the gap is still too tight. It would work just fine for smokeless, I believe.

What do you mean the wedge is flush on the far side?  The wedge has radial blends(broken edges) where the tapered edge meets the far side.  The far side is also a large radius and not a flat edge.  What feature are you saying is flush?

~Mako

[Coffinmaker]

Bob,

The first step is to resolve the barrel fit problem.  You really can't do anything else until the barrel fit is correct.  If the barrel is tight to the cylinder at the top and open at the bottom, the arbor fit is still wrong even with the 5mm split washer.  I'd suggest adding a solid brass flat washer under the split washer and turn the barrel on the arbor without the cylinder in the gun.  The bottom of the barrel assembly with the holes for the locator pins should line up on the same plane as the end of the frame with the pins.  Actually, it should do that with the split washer alone.  A small gap (.001/2) is OK, but NO overlap.
Your getting real close to the point where the head space and and end shake are going to be way out of tolerance.  If you have to add the brass washer you may want to consider sending the guns back.  If you have to space the barrel this far out, you'll need a new cylinder to correct the headspace and end shake.
So .. if you get correct barrel fit, reassemble with the cylinder, tap the wedge in snug and check the barrel/cylinder gap and the head space and end shake.  With correct barrel/arbor fit, and good head space and end shake, if the barrel cylinder gap is still too tight, it's time to remove a little metal from the back of the barrel.  .006 - .008 is good for barrel/cylinder gap, BP or smokeless.
Keep us posted.

Coffinmaker

[PvtGreg]

Hi Barrelhouse Bob,

I'd recommend that you take it to a gun smith you trust, unless you are a gunsmith or you have better smithing skills than your ordinary shooter.  I had a RM conversion that had the exact same set if issues and after some desktop messing around with it I sent it to a buddy thats a gun smith. 

Either way good luck brother because if you bought it from Cimaron you're stuck with it! Cimaron doesn't honor their own return policy.  I bought a new Spencer from them that wouldn't cycle out of the mag - my dealer & I called Cimaron and they basically said it was my problem not theirs and then hung up on us.

Gotta love Cimaron's customer service ethic!

Pvt Greg

[Mako]

I'm speechless...

[Coffinmaker]

Well ..... hoodathunkit

Coffinmaker

[Barrelhouse Bob]

Sorry to have taken so long to reply to all the good advice. Shortly after posting my first message, we discovered my wife had cancer. Her surgury is now over and we are slowly returning to a normal life.

I took the RM conversions to a gun smith friend  and he opened the cylinder to barrel gap and did a action job on them for me. What a difference!! I shot my first match with them (first time shooting duelest), and they worked flawlessly.  After each stage all I did was wipe the front of the cylinder with a damp towell. Shot six stages and not a problem.

These are becoming my favorite revolvers. They are like a extension of your arm, they shoot were you point.

[Fox Creek Kid]

...I took the RM conversions to a gun smith friend  and he opened the cylinder to barrel gap and did a action job on them for me...

I will be blunt: the vast majority of gunsmiths know next to little about these guns and it is extremely rare that one needed the barrel gap opened. I have however seen many guns ruined by numbskull gunsmiths who knew nothing about these designs There was a famous one years ago on the SASS Wire who "opened up" and ruined many Uberti & ASM Schofield clones. They demanded their money back & he disappeared. I would have asked this gunsmith that if that didn't work would he buy you a new pair as I honestly do not believe that that was your problem. However, it is your money. Good luck. 

[Raven]

"With the barrel fitted correctly to the arbor and the frame; the barrel should not ever be able to be bound against the cylinder; nor should it be susceptible of being pulled off center by the wedge, even when that wedge has been drivin in "too far"."
David R. Chicoine

I have found that Italian barrel breach faces are rairly truely square. If it is binding at the top of the barrel on the colt the barrel is not fitted correctly. But, it is common to find barrels that rub at 3,6 and 9 o'clock as well. this is from the breech not being square. Obviously they wouldn't rub if the barrel was fitted correctly. When building custom guns we always throat and face the breach.

For any of you sceptics find a dozen barrels use some Dykem on the breech and run a facing tool around it, you may be suprised.

IMHO and the way I learned it in school .006 End Gap is optimal for modern smokeless revolvers and .008 is optimal for black powder. I attended and am a part time Instructor at the Lassen College Gunsmithing School and I belive one of the problems we face, and I am as guilty as any one, is applying modern standards and ideas to a 150 year old design. You know that back in the day they fixed all the problems we experience with the reproductions which is why the main stream armed public is shooting a modern automatic or wheelgun, it's called evolution. The only thing modern about reproductions is the steel they are made of and the machines they are made on. And we shoot them in a completely different way... FAST FAST FAST and put LOTS and LOTS of ammo thru them. We expect high quality and dependibility at cheap prices...don't get me wrong I like Italian guns... but you get what you pay for and an Italian gun is a step down from the quality produced by Colt in the 1860's, 70"s and 80's. Unfortunately several of the best single action smiths won't even work on an Italian reproduction. Partly because of quality and design issues (like leaving out the hammer stop and not fitting the barrel in the first place) and that the customers expectations of what it should cost to get what they want are unrealistic.
We must remember that Italian guns are assembled and not fitted

I'm done ranting from my soap box, so......back to your regularly scheduled program.

Barrelhouse Bob, Glad you got em fixed and happy shooting



Raven

[Barrelhouse Bob]

I do not pretned to know anything about what the cylinder gap should be, or anything else about Colt conversions. I just know when a revolver is a pain in the butt to use.

The gun smith I took these to is eighty years old and has had plenty of experience with black powder guns. I trust his judgement completely. When he returned them to me they worked flawlessly. As they say the proof is in the pudding. I could not be any happier with the way they perform.

[Pony Racer]

BB - i feel the same way about my local gunsmith - he is only a few years older than I but he does a great job and stands by his work.

He is quite gifted/talented with the C&B guns and OT's but also works on everything from lever guns to Aks and beyond.

Raven, I think you hit the nail on the head about cost and expectations on guns and gun work.

V/r

PR

[Montana Slim]

I recall measuring the max gap on 4 of my 1860's (2 each, Pieta/Uberti) a few months ago.......all were at .002 - .003.
I've been runnging these revolvers with better than fair results for years.

I also run BP successfully in ALL my pre-1900 cartridge revolvers...NONE have had the gap opened and all work quite well.

Come to think of it...NONE of my other C&B revolvers have had the gap tinkered with, either..... In fact, I'd say best results have been obtained with a closer clearance.

Surprizing news, eh?

Slim

[Pony Racer]

MS - not too suprising really.

The accuracy I get from my sleeved conversions is better with the traditional sites than what alot of people report so that old saying "your mileage may vary" is definitely accurate for C&B guns and how well they do or do not do with/without tinkering.

I do love my conversions and OT's

PR

[Mako]

I used to think I was really accomplishing something by running my cylinder gap tight with both smokeless and BP revolvers.

I had several Dan Wessons with adjustable barrels and I always ran them tight until we started finding we were getting premature wear on our Silhouette revolvers.  Dan Wessons were designed to run at .006" and that was the setting standard they provided, the only exception was the .357 Maximum with a gage of .004".  Some of us ran them tight because we shot in a reclining position and wanted to attenuate the gap blast, others ran them tight because it just seemed "better."  We began reading reports that you only got very small increases in velocity as you closed the gap less than .010", so we began chronographing the differences and found it to be true.  So most went back to the .006" standard gap measure provided by Dan Wesson.  A decreased gap actually increased the gap gas velocity and wore the face of the barrel, the cylinder and increased the etching of the top strap and the gas ring.  

Every once in a while I see an etched arbor on a percussion revolver and if I get the chance I either measure the cylinder gap, or ask the owner to measure it for me.  I can't say it is always the case, but in every case I am aware of to date the gaps have been running less than .006" on the pistols with etched arbors.

At one time I also built PPC revolvers, and we thought we were being really sneaky running sub .003" gaps.  One day I was talking with Ron Power and he told me he had seen some of the short cylinder conversions I had built, I was really excited about that.  He was very gracious and waited until no one else was around and then confided he had to open the gap on one of my short cylinder guns belonging to a Virginia shooter because it was getting some drag with the loads the shooter's department used.  He told me I needed to get over the "close gap voodoo" and run them at .006".  Those were wise words.

Ten years ago I still hadn't learned, I was doing the same thing with '60 Army models and trying to run them about .006".  I had switched from Frontiersman to shooting gunfighter style and had a double handful of potential trouble.  I had been shooting C&B revolvers over 35 years at the time but never under the pressure of the clock and without "alibis."

I had two well preserved original 1860s and I finally spent some time with them determining what the original intent had been for the design.  One Pistol built in 1861 has a .009" cylinder gap,  I have another produced in 1862 which is in even better shape and it has a gap which is probably  .0105".  A .010" feeler gage will go and a .011" will just start.  I did some additional research and consulted with other 1860 owners and found their original pistols ran between .008" and .012".   I have a Colt's shop manual for SAAs  and they specify a .008" gap for the Generation 2 and later revolvers (that's using smokeless powder).  There is also a reference in a copy of another shop manual I got from one of my former instructors who worked at Colt's for 40 years that the Gen 1 revolvers cylinder gap go/no-go gage was originally .008" to .010".

I finally "relearned" what they knew 164 years ago, a Colt's pattern revolver works best with a cylinder gap of about .008"-.010" for a cap gun and .006" -.008" for a cartridge  revolver with a gas ring to control the end shake.

~Mako