Colt RM Conversion or Open Top Opinions

[Old Fuff]

Well I stand corrected... At least on paper. I have yet to see a living, breathing Uberti S&W replica top-break in .357 Magnum. I suspect they are looking at the Cowboy Action Shooting market where a lot of .357 Magnum revolvers are used with .38 Special ammunition. In any case I wouldn't care to have one chambered to use that particular cartridge - if I intended to do much shooting with the Magnum cartridge.

Of course I invite others to do differently...

 

[ArmedBear]

The 1872 Open Top addressed some of the weaknesses of the Richards and the Richards and Mason conversions. The 1872 Open Top has more threads in the frame for the arbor to screw into because none of it's recoil shield was milled off to make room for the conversion plate as the Richards and Richards Masons did.

Thank you! That helps me make up my mind.

Of course, a clever replica builder could probably do something that's not visible on an assembled gun, but provides for longer purchase for the threaded arbor. But the Open Top would necessarily provide that.

Thanks!

Next major questions...

Barrel length! Go with the original 1851 length of 7.5", reputed to balance well, or 5.5"?

The SAA uses the same grip frame as the Navy, right? Does anyone know if the mainspring is the same?

 

[Old Fuff]

Yes, the Navy model backstrap and trigger guard were used on the later model 1873 Single Action Army, and they shared the same mainspring, although the original ones were much stiffer then those commonly used now.

While the base pin or arbor is more firmly mounted in the 1872 model then earlier conversions (which also date from 1871-72) this doesn't address where the real weakness is. The greater issue is the possibility of the arbor cracking at the front where the key or wedge slot is. Often this slot has square corners, which can cause stresses that encourage cracking. During the 19th century when slow-burning black powder was used this wasn't a serious problem. With mild smokeless loads it shouldn't be either. But it is something any buyer should take into consideration. Colt didn't approve the use of smokeless powder cartridges in their much stronger Single Action Army until about 1905. Yes, the current reproduction open-top revolvers are made out of better steel, but I don't know that it is that much better.

Perhaps those who don't value the Old Fuff's opinions might consider the following:

It must be noted that even though these currently-made cartridge conversions use modern steel, both the original makers of cap & ball percussion revolvers and gunsmiths doing the conversion work intended them only for blackpowder-loaded ammunition. Do not attempt to fire them with smokeless powder ammunition.

Mike Venturino: Shooting Colt Single Actions - In All Styles, Calibers, & Generations.

Suposedly the currently made Italian open-top revolvers are proofed for use with the smokeless powder cartridge they are chambered in. All this proves is that there are no structureal issues that causes a catistropic failure. It does not adresses any issues concerning long-term use with more then the lightest smokeless powder loads.

 

[ArmedBear]

Old Fuff, I do value your opinion.

And I do know that these guns are not Blackhawks, too.

Frankly, if the barrel starts to hang a bit loose, and I have to replace the arbor and the wedge pin every 10,000 rounds, I sure won't complain.

If it's every 100 rounds, or if the frame is rendered unusable, I'd be a lot more unhappy about it. I'd opt not to buy the gun.

Somewhere in between, well, that depends.

If an apparently 100% okay gun is likely to blow up, without warning, after I've shot it for a while, with .38 Special LSWC target loads, that would be a real showstopper.

I do understand that there are few guns made that will work essentially forever without maintenance, and that handguns that fit in that category are generally either .22 rimfires, or upwards of 3 lb.

I'm just trying to get a feel for where these things really fit into the grand scheme of things.

 

[Old Fuff]

Blowing up isn't an issue - or shouldn't be because the revolvers are proof fired. Sometime when I get a chance I going to look at the proofmarks and see exactly what they are proofed for. If you buy a new gun a proofhouse certificate should come with it explaining what pressure it was proofed to.

Smokeless powder burns faster, and tends to spike the pressure sooner. When he bullet hits the bore it slams the barrel forward - if it can. On a conventional revolver it usually can't, because the barrel is threaded into the frame. However in a cap & ball conversion you are totally dependent on the wedge/cylinder pin connection.

So long as a buyer understands how the system works things should go alright, but too many don't have the foggest...

 

[ArmedBear]

Comprender.

In your opinion, is the arbor or wedge likely to fail catastrophically, i.e. will the barrel shoot downrange unexpectedly?

Or will it get loose first, so that someone who knows his way around these things will notice when cleaning or inspecting the gun, and can decide not to fire it until it's been fixed?

Smokeless powder burns faster, and tends to spike the pressure sooner.

That's true. What does the curve look like?

I've been looking around, and I can't find much other than a lot of articles with qualitative statements but no graphs, etc. Do you know of any sources for some numbers?

I suppose there'd be no need for a 7.5" barrel with smokeless, but does it balance better?

Thanks again!

EDIT: looks like the base pin is the same part number on all the conversions, Uberti 0900021, but it IS a different part from the one used on the black powder 1851 Navy replica.

 

[Jamie C.]

I suppose there'd be no need for a 7.5" barrel with smokeless, but does it balance better?

I suppose that a shorter barrel would have the advantage of applying less force on the arbor, for a couple of reasons.

For one, the bullet wouldn't exert quite a much push on it due to there being slightly less time in it and bearing surface to act on. And two, there wouldn't be quite as much leverage or inertia in recoil.
( The arbor probably has as much force applied to it from the barrel trying to "lever" it out of the frame, using the bottom of the frame/barrel as a pivot-point, as it does from the bullet trying to force it straight out. )


J.C.

 

[ArmedBear]

I don't have a Colt Navy, though, so I'm not sure how it feels to shoot.

I have a couple Remmies (early small grip and later standard grip replicas) and a Rogers and Spencer. VERY different from Colts of the day. I also have a .357 SAA clone with a 4 5/8" barrel, which is a hair too short IMO, but carries nicely.

I'm wondering if, ignoring all other factors, I'd rather shoot a 7.5" or 5.5" version of the open top.

 

[Jamie C.]

'Bear, there's only one sure way to find out...

Buy both.


J.C.

 

[Old Fuff]

Usually the wedge doesn't fail, the base pin (arbor) does. A crack may start at the corners of the slot. If not detected the front of the pin will seperate from the body of the pin, and then nothing is holding the barrel onto the frame except friction.

The pressure curve of any powder depends on the burning rate, how much powder there is, and sometimes barrel length. Most smokeless powder is progressive burning, which is to say it burns faster as the pressure increases. If the data is available, you can get some understanding by looking at the muzzle velocity of a given cartridge and load out of a 2", 4" and 6" barrel.

It should be pointed out that these Italian reproductions have been around for awhile, and not earned a reputation for blowing their barrels off. On the other hand I believe a large number of them that are being shot on a regular basis are owned by cowboy action shooters who use conservative loads in the first place. What is needed is common sense, and an understanding of what the potential trouble might be. With cap & ball revolvers I always make a point to inspect the front of the base pin whenever I clean the gun. I prefer the Single Action Army for shooting cartridges, but I will admit that an open-top from Cimarron is under consideration.

History tells us that the only reason the open-top cartridge revolvers were made was because Colt's had a huge inventory of cap & ball parts left over from the Civil War, that they wanted to use up rather then junk - and it took them into the mid-1880's and later to get the job done. When the surplus parts were used up production ended. On the other hand the U.S. Navy had all of their serviceable 1851 models converted to .38 Long Colt (black powder load) during the early 1870's, and didn't replace them until 1888. When you realize that all of them were used guns in the first place that says something.

 

[ArmedBear]

Interesting ballistics data I've been perusing.

The spec for Remington UMC LSWC ammo in .38 Special is 158 grains, 755 fps. That seems to be ubiquitous ammo around here.

Interestingly, both Ultramax and Black Hills "Cowboy" .38 Special is loaded a bit hotter than that.

Ten-X smokeless CAS ammo ranges from a bit slower with 158 gr, to a lot slower with 130 or 105 grain. I wonder if 105 grain bullets with MV 593 fps will knock down CAS targets reliably.

For my money, I think I'd stick with the much cheaper UMC.

One way or another, it appears to be easy to get inexpensive, conservative .38 Special rounds, even without handloading (which is getting more intriguing).

Usually the wedge doesn't fail, the base pin (arbor) does. A crack may start at the corners of the slot

Makes sense. Thanks. That'd be good motivation to clean and inspect it regularly.

One thing those old Colt BP designs do have going for them: they're made for easy cleaning.

 

[Jamie C.]

It sounds like taking a small needle file and rounding up the inside corners of the slot in the arbor, especially at the front, would go a long way toward eliminating the stress risers that allow that area to crack or break.

It wouldn't take much, and I doubt the material removed would make for any significant loss of strength, but it would certainly go a long way toward dispersing the stresses that'll cause problems.

Still without any modification at all, I'm thinking it would take an enormous amount of "standard" .38 spl. to cause any real problems in an open top replica.


J.C.

 

[Old Fuff]

Rounding the corners may or may not be a good idea. If you make the slot longer the wedge probably won't fit tightly. You may also find that the base pin is case hardened, and if so it won't do your file any good.

Sometimes it's best to leave things as they are.

As for ammunition, If I get one I'll use .38 Special 148-grain mid-range target ammunition, or duplicate .38 Long Colt loads using 145 to 150 grain bullets.

And keep a close eye on the front of the base pin.

 

[Jamie C.]

Fuff, I'm not talking about a huge radius here... just putting a very shallow "trough" in the corners, without really touching the flats at the end. Something on the order of a 64th of an inch (or less) radius should do it.
Bigger would be better, but that area's already pretty thin, so the less material removed, the better.

Here... this is a quick sketch of what I'm talking about:

The top view is the unaltered slot. The bottom is the slot with radiused corners, and an enlarged detail.

"Breaking" the corners like this will slow down or stop most stress-induced cracks.


J.C.

 

[ArmedBear]

If you look at Uberti's drawing above, it appears that the slot is actually oval-shaped, and that there is a good deal of metal surrounding it.

Obviously, the more metal the better, but it doesn't seem like it's hanging on by a hair or anything, should you want to tweak the shape of the slot.

The casehardening, on the other hand, is a different issue.

 

[shotgunmessenger96]

I,m glad sombody brought up the topic 'cause I,ve seen the cimarron Richards Transition Model OT revolver and was wandering if it would hold up to modern smokeless factory loads or if it could handle the .38+P rounds made for personal defense.
It IS a $500 gun so it should be sturdy.

 

[shotgunmessenger96]

http://www.cimarron-firearms.com/Conversions/TypeIIRichConv.htm#

 

[scrat]

This is an old thread. ok here is my take.

1. i would not send out my gun to get transformed. If anything you could do the conversion with a Kirsk cylinder yourself.

2. i would not even get a kirsk cylinder.

Why would i want to loose the loading lever and change the gun from its original form. Top strapless guns are awesome. All i have. However i use R&D cylinders. Why. because i can load up my WALKER to 55 grains of goex behind a round ball. Cap the nipples and shoot 6 rounds. Quickly remove the wedge, Give the Arbor shaft a wipe. Put in the R&D and shoot another 6 rounds of 45 colt.


Now another person i believe on post 15 brought of the WALKER loads. The WALKER can shoot up to 55-60 grains of goex (shooting Cap&Ball). Switching the cylinder to fire cartridge gives you a 45 COLT. 45 Colts hold 35-37 grains of goex behind a lubed bullet. So drawback is you fire a smaller load. Shooting these loads in BP is actually not bad and easy on the gun. You should never shoot regular or +P loads out of any bp gun. Even on a .36 caliber round ball. Shooting 38s needs to be very light loads. Either load them old style black powder up against the bullet no air gap. OR use a bp friendly smokeless powder. The best absoultely best smokeless powder to use in a black powder revolver is TRAIL BOSS. However even trail boss can be bad on a black powder gun if you shooting max loads. When shooting and or reloading with trail boss you should always start out at starting loads and keep them there. The wear and abuse on the gun using a heavier load is never recomended. I personally would never recomend any other powder than trail boss. For one if you reduce the powder that much to give you a lighter load you usually will have a fair amount of ftf. As there will hardly be enough powder. Thus the powder may not make contact with the fire coming from the flash hole. This is why trail boss is highly recomended. not only is it gun freindly. Its a cherrios style load round circles take up more space in the cases a 6 grains load of trail boss will fill a case a lot more than a 6 grain load of another powder. Hope this helps out. Be carefull when using cartridge conversions.

 

[Tommygunn]

Even on a .36 caliber round ball. Shooting 38s needs to be very light loads. Either load them old style black powder up against the bullet no air gap. OR use a bp friendly smokeless powder.

I own a Colt Richards-Mason Conversion (Uberti) chambered in .38.
I have never shot regular .38 special in it (mainly because all I have are FMJ or hollowpoint rounds) but I have fired "Cowboy load" .38SP.
Are those OK?
I decided to use Ten-X .38 Long Colt with blackpowder loads, or .38 Short Colt, which are also Ten-X but for some reason use modern smokeless powder (but a REALLY LIGHT load). The short colt rounds are almost amusing to shoot because they go more like "POP!" than "BANG!"
But as I said, would Cowboy load 38SP be OK or should I stick to the BP loaded Long Colt?

 

[scrat]

Cowboy loads are ok.

 

[jamesb]

I have the cimarron man with no name conversion. I love it. It handles like a 51 navy and is well balanced. I shoot cowboy loads through it and have yet to jam the cylinder or knock my wedge loose in a shooting session. My friend, CAPTMAC, has a schofield in .357. I have shot that also but it did not point well for me and felt awkward. I like the cimarron almost as much as I like my colt SAA. It was a great comprimise because I had wanted to get into BP but do not have the space for it at the moment, also helps I have Win94 in 357 I can shoot 38s out of it to pair it up with the conversion.

 

[TEDDY]

break open

well I am far removed from the posts on break open revolvers.I had many as a boy.and have a couple now they are MUCH smaller than the new ones.none were bigger than 38 S&W except the 44 bulldogs and 38 long colt and those were in solid frame.I think the rem are best because of the solid frame.why would you want to shoot cart in these guns.as soon as they could they got rid of those conversions.I never saw one and I lots of colts and rem.also IVER and H&R an blue birds.thames ect.

 

[mike101]

Kirst to the rescue

http://kirstkonverter.com/

Kirst is now making .45 Colt cylinders for Walkers and Dragoons. They make them for Colt Armies and Navies, pocket pistols, and both Remingtons, and loading leaver assemblies that drop in. You could make your own Richards Type 1 Conversion easily. You can even send it out to River Junction and have them do the loading groove for $70.

http://www.riverjunction.com/kirst/Portingservice.html

 

[owlhoot]

To get back to Bear's original questions, I have eight years experience with shooting a pair of .38 spec. open tops. The following are my observations:

I have close to 20,000 rounds through each open top shooting smokeless hand loads with 158 gr. bullets at 750 fps.

I wouldn't hesitate to use standard commercial loads such as you describe. And have put a couple thousand such rounds through the guns. However, I would not use anything hotter. Certainly I'd stay away from +P.

For the past couple of years I've been shooting BP and substitutes exclusively in the open tops. I have 5 to 6 thousand rounds through each. These guns are the perfect BP cartridge revolvers. With the big cylinder pin they just don't gum up.

The stress cracks Old Fuff mentioned can result with excessive battering, but it would take a very high pressure loads to cause that problem with modern steels. Although the problem could be helped along with a poorly fitted wedge pin, and Uberti is not very careful about fit. But even with a less than perfect fit, battering isn't apt to be a problem if you stick with standard velocity loads.

I did launch the barrel down range a couple of months ago. My wedge pin was loose evidently. The barrel went only a few feet. I don't know where the wedge pin went, never found it. Anyway, the point is that nothing "catastrophic" is going to happen except in the embarrassment.

The sights on these revolvers are about as bad as you will ever encounter. But it doesn't matter. You will get used to them soon enough. The revolvers are very accurate.

My guns were early production and they had their problems initially. However, I believe current production guns are better than mine were. My guns had a tendency to over-rotate the cylinders when speed cocking. The factory covered up the problem by installing very heavy main springs, too heavy to permit really fast cocking. When I substituted Wolfe springs, the trouble began. Precise adjustments to the hand solved the problem. I haven't heard of this problem with the newer guns. But it was common with the early ones.

By the way, when I say "speed" cocking, I'm still talking about cocking with the thumb of the shooting hand. I would not do speed cocking with the thumb of the off hand.

The ejector rod was designed to knock out .44 caliber cases. It doesn't line up well with the smaller .38 case. I fixed this by grinding a flat on the ejector rod for the first couple of inches. Problem solved.

I've had no problems with these revolvers after the initial ones mentioned. I have had to replace the hand spring in each (easily done and only a $2.50 item) And I have replaced the trigger/bolt springs in each. Another easy and inexpensive replacement that anyone can do. The main springs are still fine, but I keep a spare set of springs in my range box just in case.

My guns have the 7.5" barrels. They just look better to me. But I have shot the 5.5" barrels a lot and they handle and balance and point just as nicely as mine.

I have the navy grips on my guns but I do have an 1860 Army and I like the Army grip just fine. If your hands are large, you might prefer the Army grip. I went with the Navy grip because it is so much easier to get main springs and aftermarket grips if needed. Besides I was used to the Navy size.

I have some experience with both the Richards and Mason/Richards conversions. They feel and handle just like the open tops. I'd love to have a set, especially the Richards.
I don't know if they are as dependable as my OT's have been, but I'd guess that you would be happy with your choice whichever you decide on.