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Don Williams
July 22, 2008, 13:15
I've got a couple 45 colt revolvers that I'd like to get 45 acp cylinders for. What is involved in swapping cylinders with regard to timing issues? One's a Blackhawk and the other is a model 25 Smith.

hockeysew
July 22, 2008, 17:11
Seeing how they are both the same caliber it should be as easy as a cylinder swap. If the timing is ok on the 45LC it shouldnt change on the .ACP.
A quick check would be to turn a piece of round stock to where it is a slip-fit down the bore. It should enter the chamber easily on each of the six.
You might want to do the paper test on the cylinder sides. Hang a couple of sheets of white paper a few inches away from the cylinder/frame gap on both sides and fire the weapon. Use a rest if you are really worried about it. If you see signs of lead shavings you have an issue.

win308
July 22, 2008, 19:44
The spare cylinder for the Ruger should be easy enough....it is a replacement part. The Smith will take some careful planning, as the correct 45 acp cylinder will have to fit right up to the barrel so as to not have excessive gap.
The first picture is a model 25-5 in 45 Long Colt. Notice how far the barrel screws into the frame and out the other side until it just about touches the cylinder. Then look at picture nr. 2, which is a 625-4 in 45 acp and observer the same thing...the barrel goes much further in until it comes close to the 45 acp cylinder. A swap of either cylinder into the other frame just will not work. It will take more than a spare cylinder in 45acp to accomplish what you want with a S&W.

http://i32.photobucket.com/albums/d1/win308/1111.jpg

http://i32.photobucket.com/albums/d1/win308/2222.jpg

GOVTMOD
July 22, 2008, 19:52
Sleaving the chambers wouldn't work at all. Just cause a ton of headache and a potintially dangerous situtation if one of the sleaves decided to dislodge and obstruct the bore and/or lodge itself in the forcing cone.

The timing on both of these revolvers is the relationship between the hand and the cylinder locking bolt and how they align the chambers with the forcing cone. In order to make the LC and ACP cylinders interchangable and time correctly they would have to be fit to their respective frames by a good 'smith or the factory.

They do have ACP cylinders designed for LC 25s they just have more time in the chamber before they get to the forcing cone.

BUFF
July 22, 2008, 20:59
Win308's excellent photos illustrate the problem of trying to get a convertible double-action S&W.

S&W has made .45 Colt revolvers with two different cylinder lengths. The Model 25-3 and -4 (made in 1977 only) have the same, shorter cylinder length used in their .45 ACP guns, while the Model 25-5 (introduced about 1981) has the longer cylinder, the same length as the .44 Magnum Model 29, basically. S&W used to stock the short cylinder, but chambered in .45 Colt, to be fit in the 1955 Target/Model 25-2 .45 ACP, but you had to know somebody to get one installed and it wasn't cheap.

It isn't just the front end of the cylinder that is different, the back ends are also. The .45 Colt has a very thin rim and the distance from the frame's bolt face to the rear of the cylinder is much, much smaller than the space on their .45 ACP guns, which need a space ther equal to the thickness of the .45 ACP's rim plus the moon clips. If you cut the cylinder stop lug for the Colt, the ACP clinder will flop around when the gun is open.

There are ways around this, but they are all expensive. I had the late Andy Cannon fit a .45 Colt cylinder to a .45 ACP M-25-2. I started with the longer .45 Colt cylinder from the M-25-5. Cannon cut the front face of the cylinder down and fit the ejector's ratchet to the revolver's hand. To deal with the rear, he cut a 45 degree recess around the outside of the rear of the .45 Colt cylinder deep enough to clear the cylinder stop lug on the frame.

Basically, he fit the new cylinder to the gun, never cutting anything on the revolver so the original .45 ACP wouldn't be affected.

This cost me as much as another Model 25-5 would have cost. I wouldnt do that today.

Fitting the new cylinder on a single action is easier. I had extra ones fit to a couple of Colt single actions at the factory (a .44 Special cylinder for a New Frontier made in .44-40 WCF and one in .45 ACP for a S.A.A. in .45 Colt) , and the work was reasonably priced. My wife found the cylinders on EBay. Ruger should be less.

bykerhd
July 23, 2008, 00:01
This is a friend of mine's 25-7. He bought it off GunsAmerica I believe.
I don't know who modified the cylinder. Or, if it was done by S & W ?

It takes the original .45 Colt cartridges as well as the .45 ACP in the moon clips.

hockeysew
July 23, 2008, 00:07
Originally posted by Don Williams
I've got a couple 45 colt revolvers that I'd like to get 45 acp cylinders for. What is involved in swapping cylinders with regard to timing issues? One's a Blackhawk and the other is a model 25 Smith.

What exactly did you mean by timing?
As it was well explained above timing is the relationship of the cylinder chamber to bore, as controlled by the hand and held by the bolt. That was my take on your question.
From some of the replies it sounds as if you are more concerned as to the cylinder length/gap.
I know on my Cimarron Model P it is as simple as swapping cylinders.
Just curious if I missed something and led you astray.
Sorry if I did-Heavily medicated from surgery yesterday:sad:
Double hernias suck!

Don Williams
July 23, 2008, 11:06
by timing I was concerned with having the cylinders out of alignment enough that I would have to re-cut the forcing cones to preclude shaving lead and/or gilding metal. I think the Ruger will be a drop in but with the Smith what I'm probably going to have to do is get them to install a another 45 Colt cylinder and send the new cylinder to Pinacle and have the moon clip conversion done on it. I don't want to cut the original cylinder on this gun.

Here's their link for those who want more info on this:

http://www.pinnacle-guns.com/revolver.asp

GUN SNOB
July 25, 2008, 11:18
I have a 45 colt Redhawk and thought a ACP Cyl. would be cool.

My plan was to start with a 44 mag Cyl and rechamber to 45acp and cut for moon clips.

If your cyl is the same over all length and you dont have to cut on the ratchet face to establish head space then TIMING should be just a matter of propper fitting. (hand, paw to ratchet fit) Since the cut for the moon clips depth will establish head space and cyl gap is established by OAL I should be corect in theorie,,,,Right?

You still want the cyl to line up with the bore. Changing the forcing cone to compensate for misalinment will still have the bullet slaming in to the edge of the barrel deforming the bullit and adding to the stress (batering) on the frame. The reason for propper timing is to reduce this as much as possable with in the stacking of tolerances. (side movement in the cylinder at lock up)

rdc01
August 23, 2008, 08:04
What he said..cut it for moons


Originally posted by bykerhd
This is a friend of mine's 25-7. He bought it off GunsAmerica I believe.
I don't know who modified the cylinder. Or, if it was done by S & W ?

It takes the original .45 Colt cartridges as well as the .45 ACP in the moon clips.