1858 Remington.Kirst 45 ACP conversion

[44Vaquero]

I finally got around to cutting the loading port in the recoil shield! Having reviewed other shooters efforts to port their guns free-hand with mixed results. I opted to build a jig fixture to hold a small air moto tool and clamp the revolver in place for cutting.

I am quite pleased with the results, and looking forward to porting this revolvers mate very soon!

As for load development I have just received my Cowboy 45 Special brass and Barnstormer 125gr HB Boolets and have a Lee 160 gr mold on order. Should be interesting!

[lathesmith]

Nice work 44! I'm kinda partial to these gated Kirst Konverters myself, and the '58's make fine 5-shooters. I free-handed mine, I got excellent results, although I uncovered a hidden flaw in the metal of my Uberti Cattleman's carbine it still worked well. I also built my own ejector rod housings, with some welding help from my late father. However, I do like your jig, and I'll also be interested in your 45 Cowboy Special loads; I have some of this brass myself, but have not had a chance to work with it yet. Good luck, and keep us posted on your results!

lathesmith

[44Vaquero]

Lathesmith, Thank you for the kind words. I was impressed with the Kirst's ease of install and good fit on the 1st try!

The Barnstormer II cast bullet from Adirondack Jack is what I really want to work up a nice load for. I like hollow base boolits. I plan on keeping this thread going until I have both guns finished and several loads developed.

I like the idea of making your own ejector rod and housing. A couple of close up pics might help a guy out?

[EMC45]

Very clean work 44Vaquero. Looks factory!

[Idaho Sharpshooter]

EMC45,

I don't mind dying, I just don't want to be on the next flight...

Those conversions look very nice.

Rich

[44Vaquero]

I now have a couple hundred Cowboy Special's and .45 A.C.P's loaded up and I am headed to the range on Monday. This will be the 1st field trip with the Kirst Conversion.

I whipped up a period style cartridge box to go along with this project, it's not a dead on reproduction, I only wanted to capture the sprite of the west. I think it turned out pretty good.

[44Vaquero]

Wow! What a blast to shoot, this Remington is going to become my favorite revolver very fast! The action is slick and the trigger pull is light, shots were centered but printed very high about 6 inches @ 25 yards.

Since this was an informal outing once I figured out a 6 o'clock basement hold was required we moved to the 6 inch spinner and coffee cans for fun! As long as I did my part neither were safe!

Then I got out the Chrony and ran a few strings over the screens:

130gr Barnstormer Mark II .45 CBS 4.3gr Trail Boss 764 fps STD D 23 fps
Easy Shooter

200gr BBWC .45 ACP 4.3gr Trail Boss 742 fps STD D 17 fps
Rings real nice when you hit the spinner

Not too bad for starting loads now I can start to fine tune the load development.

[SMPARKINSON]

Nice work 44! I'm kinda partial to these gated Kirst Konverters myself, and the '58's make fine 5-shooters. I free-handed mine, I got excellent results, although I uncovered a hidden flaw in the metal of my Uberti Cattleman's carbine it still worked well. I also built my own ejector rod housings, with some welding help from my late father. However, I do like your jig, and I'll also be interested in your 45 Cowboy Special loads; I have some of this brass myself, but have not had a chance to work with it yet. Good luck, and keep us posted on your results!

lathesmith

Well I thought I was the only one! While I was cutting the port in my Uberti carbine I came across a void in the casting too! I was hoping it was just a very small bubble, but it didn't look like I would get past it even if I cut a little deeper than I wanted to. So I stopped at my planned depth and decided that I will have to live with the void. It's not all that large, and I have shot it and not seen any evidence of any cracks forming in that area or any other reason for concern. I also have an Uberti 1858 revolver that I cut for the port, and found no such void. I really can't understand what it is about the carbine frame that might make the casting predisposed to this type of flaw, but it sure is interesting that I'm not the only one. I wonder how prevalent this flaw in the casting is in these carbine frames. Probably very few of them are cut in this area for a loading gate, so the fact that we both found the same problem would lead me to believe that it is probably more common than we might think. I guess maybe Uberti should either magniflux or xray these frames for quality control and see how often they find it. For me it isn't a problem aesthetically due to the fact that I have already antiqued my carbine to an old looking grey gun look, and if I fill the void with JB Weld and polish it up it will probably be about invisable. I would sure like to hear from anyone else who has had this issue come up when they cut the metal in this area of their Uberti carbine frame.

[44Vaquero]

I have heard about possible voids in the castings of Uberti's as well. My suggestion would be to fill the void by laying a welding bead in it and grinding it flush after words. The frames are only mild steel and are not heat treated so it is a fairly simple fix.

[John Taylor]

I have heard about possible voids in the castings of Uberti's as well. My suggestion would be to fill the void by laying a welding bead in it and grinding it flush after words. The frames are only mild steel and are not heat treated so it is a fairly simple fix.

I would recommend TIG welding. There is no room for an arc welder on guns.

[JIMinPHX]

shots were centered but printed very high about 6 inches @ 25 yards.

That seems to be fairly common with the old C&B revolvers. I've been told varying reasons why that might be. The most common explanation seems to be that it's because they were originally sighted for long range use.

That's a nice sensible jig you came up with there & some very nice results. My compliments.

[44Vaquero]

I am willing to live with the shooting high. Overall I was pleased with the performance of the loads made with Trailboss.

My next trip out to the range will be with what I am hoping will become the mainstay of these revolvers. I have been busy casting Lee's 160 grain .45 boolit. I have just finished pan lubing and sizing up a few hundred of them. I will admit pan lubing them has been a challenge as they are very short boolits and the distance between the lube and crimp groove is very short! But I wanted to give it a try.

Results to follow soon!

[JIMinPHX]

Overall I was pleased with the performance of the loads made with Trailboss.

Trailboss?!?!? I thought that those things were made for black powder only & specifically NOT smokeless powder because of the pressure. As far as I know, a cylinder conversion doesn't change that. Are you aware of some information to the contrary?

[44Vaquero]

No, They are rated for "Low" pressure(Lead only, no jacketed) loads under 1000 FPS. That's fairly wide margin of safety in the 45 ACP. The .45 ACP operates at a relatively low maximum chamber pressure rating of 21000 psi (145 MPa) (compared to 35000 psi/240 MPa for 9mm Parabellum). Hell, the loads I listed above did not even expand the brass much, when I opened the loading gate the brass just falls out!
Walt and Raven build a quality product and are fantastic gentlemen to deal with. I follow their recommendations in relation their products!

[JIMinPHX]

So then, the cylinder conversion manufacturer suggested that loading data????

[JIMinPHX]

I don't have a lot of black powder pressure data, but pages 41-42 of the Gun Digest Blackpowder Loading Manual 4th edition lists a 100-grain FFG charge of GOEX behind a 370 grain maxi-ball in a rifle producing 1375fps from 13,500psi. That is a lot bigger boolit & a lot bigger charge of powder than you could possibly fit in a C&B revolver & it doesn't even come close to the pressures that you are calling relatively low.

I'm not saying that you are going to blow the gun up using that load, but I am saying that I think it would be prudent to confirm that it is a safe load to use before you get going with it. Even if the cylinder is made out of a strong material & the chambers can take the pressure, other parts of a gun, that was designed for black powder only, might not be up to the task.

Maybe other guys have been doing that for years with the cylinder conversions & maybe it's perfectly safe. I don't know that for sure one way or the other.

If the cylinder manufacturer recommends that load & other people have been using it successfully for some time now, then all is probably well.

I think that it is worth looking into if you don't already have reliable information on the subject.

[44Vaquero]

Much ado about nothing! Where people get into trouble with conversion cylinders is when they try to make them Magnums or load jacketed bullets. They will shoot loose, stretch the frame and possibly split the forcing cone. This guns are not heat treated and the forcing cones were never intended to swage copper jackets.

Cowboy loads are generally loaded to about 750 FPS regardless of bullet weight.
"Trail Boss" is the perfect powder to work with in this application as it was designed to be a bulky case filling powder intended for Cowboy action shooting.

Hornady, Winchester, Ten-X, Mag-tech etc, all manufacture smokeless loads intended for the Cowboy action shooting.

JiminPHX you may want to check out http://www.cascity.com and visit their forum page lots of treads about safe reloading for conversion cylinders.

From the "Kirst Konversion" web page:

"All Kirst Konverters are precision CNC machined in the USA from 4140 Steel and heat-treated. The cartridge conversions are rated "For Black Powder or equivalent loads only," which includes the current Cowboy Loads on the market.

Caution:
Ammunition must be loaded with lead bullets and a low-pressure, powder charge that DOES NOT EXCEED 1000 FEET PER SECOND VELOCITY!
NOT FOR USE IN BRASS FRAME REVOLVERS!
.44 and .45 caliber cylinders must NEVER BE INSTALLED IN A .36 CALIBER REVOLVER!"

[44Vaquero]

IMR's Published data: 45 ACP
Bullet Weight (Gr.) Powder Bullet Diam. C.O.L. Grs. Vel. (ft/s) Pres Grs. Vel. (ft/s)pressure

180 GR. LFP IMR Trail Boss .452" 1.140" 3.5 664 7,100 CUP 5.0 852 13,700 CUP

200 GR. LSWC IMR Trail Boss .451" 1.225" 3.5 652 9,200 CUP 5.5 816 16,100 CUP

230 GR. LRN IMR Trail Boss .452" 1.200" 3.5 658 11,200 CUP 4.5 761 15,100 CUP

The 45ACP SAAMI Maximum Average Pressure (MAP) is 18000 C.U.P. and 21000 P.S.I. in standard pressure loads.

[JIMinPHX]

Howdy Vaquero,
It sounds like you've been through it. I'm sorry if I stirred up a bit of a hornet's nest there. I just wanted to make sure that you weren't running off blindly into uncharted territory. Being as I don't know you & I hadn't seen loading recommendations for the conversion cylinders before, I was concerned that might have been the case. Hearing about the voids in the frames compounded my concerns to some extent.

Sorry for all the fuss,
Jim

[john hayslip]

I wasn't aware of the Kirst Konversion til the other day when I saw an ad for them and went to their website so I've never used one. I did however convert a petersoli using a conversion cylinder from Taylor's that has a removable rear portion of the cylinder and 6 firing pins in it that are hit by the original hammer. Have to remove the cylinder to reload but works fine. It's in 45LC - sold it and got an 1875 with dual cylinders 45acp/45Lc that works rather well as long as you get to the range with the proper cylinder for the ammunition you have (I think you can probably guess why I make that recommendation)