Choice for Conversion or OT

gunboat57 · January 04, 2012, 03:14:31 PM

Howdy all. I am new to the world of cartridge conversions though I've shot cap and ball revolvers for years. My plan is to get either an OT or cartridge conversion and shoot with black powder. I've done some research on this forum and here's what I think the situation is:

If I want a Uberti and I want it to be close to the originals in cylinder diameter, chamber circle diameter, etc., then my only option is the "1851 Navy Conversion" in 38 Special.

Do I understand correctly that the Uberti OT in 38 Special is now made with a cylinder large enough to chamber the 45 Colt? Or does Uberti make the OT in 38 Special with a cylinder diameter more like the original Colt OTs and not so much a "Frankengun"?

Still trying to get it all straight!

Hoof Hearted · January 04, 2012, 08:20:11 PM

The Uberti "1851 Conversion" commonly called the 1851 Richards mason is pretty close (close enough) in size, heft and balance.
The main difference is it is in a modern chambering utilizing inside lubed ammo (commonly available).
http://cimarron-firearms.com/Conversions/51R-MConvOpener.htm

The Uberti OT "Opentop" is not actually a "conversion" as it was designed to be a centerfire firearm from the get and go. It utilized the 44 in rim fire configuration originally so it was designed to have a larger cylinder then the '51. It too is pretty close and you can get it in either the Navy or Army grip size.
http://cimarron-firearms.com/OpenTop/OpenTop.htm

The only Uberti that is noticeably oversize is the 1860 Richards Mason. It was redesigned to allow six 45 cartridges in it's bore circle.
http://cimarron-firearms.com/Conversions/60-R-MConvOpener.htm

Of course you can obtain a "drop in" conversion for your 1851 or 1860 (this will keep the size and heft as close to original as possible).

gunboat57 · January 04, 2012, 09:37:53 PM

Thanks, Hoof Hearted. You cleared up some foggy areas. Based on what you said, an Open Top in 44 Special with 7.5" barrel and Army size grips sounds mighty attractive. I already reload 44 magnum and could use the same dies and bullets.

I started looking into the various Uberti conversion and OT models almost a year ago but spent my funds on a 44-40 New Service that happened along. Just couldn't resist. Gotta stay focused.

Hoof Hearted · January 04, 2012, 10:15:41 PM

That would be a MIGHTY nice package!
If you are looking for authenticity, I'd steer towards the Cimarron.
They tend to keep 'em clean (proofs hidden, font on bbl legend looks period).

HHMB

Long Johns Wolf · January 05, 2012, 04:18:33 AM

Sorry HH & FWIW I disagree regarding the Uberti Navy 1851 RM: it is beefed up like Uberti's Army Richards Transitional (R2), Army Richards-Mason and the OT.
In addition their Navy & Army RM and the R2 feature that same gas ring as the OT. Which is period correct on the OT and very, very useful when shooting black powder in combination with the right lube ... but it is not PC on the conversions.
Long Johns Wolf

Hoof Hearted · January 05, 2012, 07:55:13 AM

Quote from: Long Johns Wolf on January 05, 2012, 04:18:33 AM
Sorry HH & FWIW I disagree regarding the Uberti Navy 1851 RM: it is beefed up like Uberti's Army Richards Transitional (R2), Army Richards-Mason and the OT.
In addition their Navy & Army RM and the R2 feature that same gas ring as the OT. Which is period correct on the OT and very, very useful when shooting black powder in combination with the right lube ... but it is not PC on the conversions.
Long Johns Wolf

I said:
"the 1851 Richards mason is pretty close (close enough) in size, heft and balance."

Good point on the gas ring! Some like it, some hate it, but it's there and SHOULD help with fouling

Long Johns Wolf · January 05, 2012, 09:20:23 AM

As a "side issue" so to speak and I don't wish to hijack this thread: Among the FROCS here in the Rhein-Main-Area in Germany we are currently executing a broadly based feasibility/function study on C&B pistols of .44 cal. vs. modern made factory and conversion artist conversions used in CAS.
The C&B pistols are loaded with BP while the conversions are fed with both nitro and BP cartridges.
Among other things each conversion is fired with 6 strings of 5 rounds of smokeless and BP respectively, without major cleaning between the strings. We feel that this about represents what a cowboy or cowgirl is firing through one pistol during a typical day of CAS.
The whole program is set up in a standardized way to be able to draw useful conclusions and provide recommendations at the end of the day. Yesterday the tests on the conversions were completed. After this long winding intro I like to share a few observations regarding lubes and gas rings.
NB: I am regularly shooting C&B pistols in bulls eye only but my conversions in CAS competition with smokeless loads.
My favorite, all purpose cleaning, preserving and lubing agent was MoS2 spray for the last 40 years for all my pistols and rifles. Never no problem.
Until I used my conversions with MoS2 lube & loaded with BP cartridges in this test. The Remmie custom conversion was disabled by BP fouling after the 2nd string, the Centaure Long Cylinder custom conversion and the Uberti 1860 Army RM conversion were disbabled by fouling after the 3rd string. Could no longer turn the cylinder even supported by the left hand.
Contrary to my experience my shooting buddy Socks was firing string after string with his Uberti OT without any problems.
On the other hand my conversions performed without issues with smokeless ammo ... as did Sock's OT.
Obviously the lube made the difference. He used vaseline based stuff whereas I used the MoS2.
Preliminary conclusions: vaseline base lube is fine for smokeless and BP, MoS2 lube works fine with nitro loads AND as cleaner and preserving agent ... and for bulls eye shooting with BP loads where the pistols are not getting too hot.
Next phase of the test: lubed my conversions with Sock's magic vaseline stuff. here is what we got: Remmie completely fouled and disabled after 1st string - probable cause mechanical problem (hand, to be confirmed). Centaure was done after 5 strings. wiped the surface of the cylinder with wet cloth and 6th string was fine. Uberti RM cocked and cylcled during all strings without any hick-up. My conclusions:
#1. if you shoot BP in a CAS match dont' use MoS2 but vaseline on your pistols as a lube.
#2. in such a scenario the conversion or OT lubed with vaseline, but equipped with a gas ring protects much better from BP fouling than the PC correct conversion without gas ring.
Long Johns Wolf

Hoof Hearted · January 05, 2012, 09:46:18 AM

Long john

Interesting stuff there!

I did not assume that the OP was overly concerned about "multiple strings" and fouling as his question was dialed more towards authenticity. This NEVER seemed to be the issue in the Old West that we have made it out to be in the "New West"

Was all just part and parcel to the time! I'm sure this was another good reason to own more than one gun........

HHMB

Long Johns Wolf · January 05, 2012, 10:18:13 AM

Hoof Hearted, cannot agree more. Support your local gun dealer, ha.
Long Johns Wolf

gunboat57 · January 05, 2012, 11:46:57 AM

Just for giggles here are some pictures I spliced together last March.

Here is a Uberti Navy R-M conversion compared to a cap and ball Uberti Navy:

It does look like the R-M cylinder was beefed up a bit.

Here's a Uberti OT compared to a Uberti 1860 R-M conversion:

The cylinder on the 1860 R-M is massive! I guess it would have to be since the rebated part has to be big enough for 45 Colt rims.

I know these pictures give only a qualitative comparison. While looking through this forum I've found Mako's measurements of cylinder diameters. That's been really helpful.

Hoof Hearted · January 05, 2012, 12:02:07 PM

Great pics!

I think they are a bit miss-leading though.
If memory serves me correct I tink we are only talking a max of around 60 thousandths greater on any one of these designs.
60 thousandths
About a 16th of an inch.

More important than that is overall feel, heft of the firearm in the context of the OP.

HHMB

Marshal Deadwood · January 05, 2012, 02:36:59 PM

I have one of the new Richard Mason Army conversions, and while I know they are a wee bit over-sized in the cylinder, I really like it. Nothing to the heft and balance that would disturb me any. Mine is in .44Colt. I had an arbor fit job done to it, and it will absolutely stack the bullets in quarter size groups now.

Deadwood

Flint · January 05, 2012, 07:24:16 PM

The Uberti Opentops and Conversions all have larger diameter cylinders than the Cap & Ball. The centerline of the breech is higher and the center chamber circle is about 1.05 inch, where the cap & ball is 1 inch. A SAA is about 1.06. This allows the chambering of 6 cartridges and thicker walls, particularly this allows the floor of the frame to be the proper thickness for the bolt.

One (of the many) problems with the ASM conversion was they had enlarged the cylinder without raising the arbor center, and the bolt went through a paper thin frame window area, making for a markedly misshapen bolt head.

The OT and conversion dimensions are reflected in the barrel assembly, so they are not interchangable with Cap & Ball parts in the frame to barrel fitting. They are not the same as a Kirst or Howell (R&D) conversion cylinder, which will only fit a C&B frame.

Being a bit larger does not affect the handling for me, my Opentops point as naturally as a 51/61 Navy, and better than a SAA, at least to me.

Long Johns Wolf · January 06, 2012, 01:16:18 AM

Thanks for this qualitative comparison. Just for the fun of it can you do an Uberti OT vs Uberti Navy 1851 RM conversion and an Uberti OT vs Uberti Navy 1851 C&B pistol.
Thanks.
Long Johns Wolf

gunboat57 · January 06, 2012, 06:42:45 AM

Long Johns Wolf, here ya go...

Here's an OT vs an 1851 R-M:

And here's an OT vs 1851 Cap and Ball:

I should describe how I put these pics together. I downloaded the images from the Uberti website. Then opened the pics side by side in Microsoft Office Picture Manager. Sometimes I had to flip one pic to make a "left hand" image. I adjusted the zoom of both pics until the vertical length of the rear of the frame where it joins the grip frame was identical for both pics. Then I used "Snipping Tool" to create one JPG file from the two pics. It's not totally accurate but it's the best I could do using the pictures available.

Long Johns Wolf · January 06, 2012, 07:05:10 AM

Thanks Gunboat I see some light at the end of the tunnel.
But now I have this senior moment and like to ask a few questions to the initiates:
#1 If memory serves in most of the original Colt Army Richards (R1) conversions when the original C&B cylinder was bored through to accomodate .44 Colt cartridges, the rear segment of this formerly C&B turned conversion cylinder has the diameter of the of the Colt Navy 1851/1861 C&B cylinder. Am I correct?
#2 The original Colt OT was build on a Navy frame and had a cal. of .44 RF. Is its cylinder diameter identical or close to that of the Navy C&B cylinder?
#3 How does the cylinder diameter of the Uberti Colt OT .44 cal. compare to the Uberti Colt 1851 Navy RM Conversion .38 cal? Shouldn't that be identical or close?
Thanks for enlightening me.
Long Johns Wolf

Hoof Hearted · January 06, 2012, 07:46:44 AM

LJW

Without getting out any books........

#1 If memory serves in most of the original Colt Army Richards (R1) conversions when the original C&B cylinder was bored through to accomodate .44 Colt cartridges, the rear segment of this formerly C&B turned conversion cylinder has the diameter of the of the Colt Navy 1851/1861 C&B cylinder. Am I correct?
Yes
#2 The original Colt OT was build on a Navy frame and had a cal. of .44 RF. Is its cylinder diameter identical or close to that of the Navy C&B cylinder?
#3 How does the cylinder diameter of the Uberti Colt OT .44 cal. compare to the Uberti Colt 1851 Navy RM Conversion .38 cal? Shouldn't that be identical or close?
The Open Top was an entirely pupose built pistol not built on the "Navy frame".

Quote from: Long Johns Wolf on January 06, 2012, 07:05:10 AM
Thanks Gunboat I see some light at the end of the tunnel.
But now I have this senior moment and like to ask a few questions to the initiates:
#1 If memory serves in most of the original Colt Army Richards (R1) conversions when the original C&B cylinder was bored through to accomodate .44 Colt cartridges, the rear segment of this formerly C&B turned conversion cylinder has the diameter of the of the Colt Navy 1851/1861 C&B cylinder. Am I correct?
#2 The original Colt OT was build on a Navy frame and had a cal. of .44 RF. Is its cylinder diameter identical or close to that of the Navy C&B cylinder?
#3 How does the cylinder diameter of the Uberti Colt OT .44 cal. compare to the Uberti Colt 1851 Navy RM Conversion .38 cal? Shouldn't that be identical or close?
Thanks for enlightening me.
Long Johns Wolf

Long Johns Wolf · January 06, 2012, 09:58:11 AM

Hoof Hearted and the campfire: thanks for the clarification ... but...
I am rephrasing my 2nd question: The original Colt OT had a cal. of .44 RF and was build on a frame with the same geometry and the same overall dimensions of the Colt Navy frame?
If I look at Gunboat's pics it would appear that the Uberti version the OT and Navy are pretty close when it comes to frame and cylinder?
Does any of you gents and ladies have originals readily available and can do some measuring, please?
Long Johns Wolf

gunboat57 · January 06, 2012, 01:03:09 PM

I'd like to know the measurements from some originals too. My totally uninformed opinion as a 35+ years mechanical engineer is that Colt would not have tooled up a brand new frame. They would've used the basic existing design and deleted any machining operations pertaining to percussion and added the cuts needed for the loading gate. Of course, I welcome correction based on facts when they come up.

I know that in one of Mako's posts a while back he listed cylinder diameters and chamber circle diameters for various modern
Uberti models. The OT had a chamber circle approx. .050 larger in dia. than the 1860 or 1851 C&B models. But they could be using the same basic frame size by cutting more of the frame away to allow for the non rebated cylinder diameter of the OT. I wonder if Colt originally did that too?

While we wait for other responses, I'm going to search for some good pics of originals and see if there are any obvious frame differences.

Update:
Here's another cobbled picture comparing an original 1860 with an original 1872.

Again, this is a qualitative comparison. But it looks like the 1872 OT had a cylinder diameter somewhere in between the 1860 cylinder rebated and non rebated diameters.

Hoof Hearted · January 06, 2012, 01:57:55 PM

Quote from: gunboat57 on January 06, 2012, 01:03:09 PM
I'd like to know the measurements from some originals too. My totally uninformed opinion as a 35+ years mechanical engineer is that Colt would not have tooled up a brand new frame. They would've used the basic existing design and deleted any machining operations pertaining to percussion and added the cuts needed for the loading gate. Of course, I welcome correction based on facts when they come up.

I know that in one of Mako's posts a while back he listed cylinder diameters and chamber circle diameters for various modern
Uberti models. The OT had a chamber circle approx. .050 larger in dia. than the 1860 or 1851 C&B models. But they could be using the same basic frame size by cutting more of the frame away to allow for the non rebated cylinder diameter of the OT. I wonder if Colt originally did that too?

While we wait for other responses, I'm going to search for some good pics of originals and see if there are any obvious frame differences.

There were changes made to many aspects of the 71/72 Opentop.
It was re-engineered to have a loading gate
A two stage pawl,
A different hammer,
The area we call the recoil shield is different,
and probably other areas not coming to mind while I type.

I am not argueing here but I am basing my opinion on what i have seen here in the shop.......your mileage may vary.
Anyone who posesses the books written on the subject should be able to quote what has been written on the subject. My summary of what I have read is that it was a departure form the existing.......