Real Colts

[Old Savage]

Fellows, will someone with a real Colt SAA measure the thickness of the cylinder walls between the chambers of a .45 Colt cylinder for me. I have compiled the measurements of a number of revolvers and would like to add this one.

[JerryB]

Well my good doctor, I got my Colt and took the cylinder out. I have an old pair of Starrett calipers and mark the first wall and went around them.I am not sure what I got but hereare the numbers. My Colt is an early second generation. I bought it in 1959,it was made in 1957. Will these read in .000 or .000 or .0000 ? the first wall is .710, .720, .670, .720, .710, and .690 these may be off so don't take them for the gospel. Maybe some one that knows what they are doing will jump in.

[Pisgah]

Well my good doctor, I got my Colt and took the cylinder out. I have an old pair of Starrett calipers and mark the first wall and went around them.I am not sure what I got but hereare the numbers. My Colt is an early second generation. I bought it in 1959,it was made in 1957. Will these read in .000 or .000 or .0000 ? the first wall is .710, .720, .670, .720, .710, and .690 these may be off so don't take them for the gospel. Maybe some one that knows what they are doing will jump in.

Pretty sure you are missing a 0 in there somewhere, unless there's a Colt out there with chamber walls between 2/3 and nearly 3/4 inch that i haven't heard about.

[JerryB]

I was not sure of the reading, I just use my old calipers to check bullets against known ones, a machnist I ain't.

[cowboykell]

1st generation = .035 - .037

[Sixgun]

OS,
I just measured the cylinder on an 1878 Colt (made 1902) (uses single action barrels & cylinders) and they miked out at .035 on the back (rim area) and the face was .070. Then I miked out a first gen Colt (made 1917) and they showed the same, + or - a thou. I do have a third gen but I got lazy all of a sudden. -----------Sixgun

[Old Savage]

OK, on the clones - an Iver Johnson and a Peitta (Heritage Rough Rider) both measured approx .060" on the outside chamber walls but the IJ measured .045" between chambers. The Pietta measured .031" between the chambers. It would seem there would be a large variance of what they could take but of course there are other variables. For comparison a Ruger BH three screw measured .070" on the outside and .060" between the chambers.

Thanks for the info. Now, if the thinnest will take the SAAMI what are the limits of the thicker cylinders? Freedom Arms is approx, .125" between chambers, slightly less to the outside - .113"

Ruger 44 Mag wants .085" on each measurement.

Colt 44 Spl SAA is approx. .065" on each. or more than twice the .45 Colt on the chamber/chamber measurement. Smith 24 is about .080" to the outside and .090" C/C.

Might as well throw in Ruger New Vaq at .082" to the outer and C/C of .060" for the 44 Spl.

[COSteve]

Don't just rely on the wall thickness because there are many different types of steel with differing strength characteristics. A thick walled mild steel cylinder won't be anywhere near as strong as a thinner walled barrel steel one. Also, older firearms were made with old technology steel that's generally not as strong as new technology. So, without knowing a lot more about the steel used in the barrel, frame, and cylinders one can't reliably predict it's strength and / or pressure capabilities.

[Old Savage]

Steve that is what I was referring to in other variations. I would assume that all modern manufacturers name would be using the best steel. ????

I do wonder what the limits are of the .031/.035 between the chamber walls and how much strength is added with the thicker tolerances of for instance the Iver Johnson Cylinder that is at .045"

[M. M. Wright]

OS,
I dug out an old thumbuster that was one of 50 shipped to H & D Folsom Arms Co. of New York on October 4,1876. Between every pair of chambers it measures .035 inch. No detectable variation with dial calipers.
The more critical measurement is the depth of the bolt cut. That outside wall measures .055 and the bottom of the cut is .052 below the outer surface. I became aware of this thin place in the early 60s when I re-cylindered one to .45 ACP. If I remember correctly, the cylinder came from Hy Hunter and the first one failed at a couple of the bolt cuts. Sent it back and they gave me a new one that lasted through many years of military hard-ball.
The people who hot-rod the single action go to 5 shooters to get that cut off the side of the chamber.