45 auto rim in a Blackhawk convertible.

Some time in the past year I read an article by John Taffin or Brian Pearce about facing the rear of a 45ACP cylinder so that 45Auto Rim may be used. Of course the ACP round still headspaced on the cartridge mouth and could still be used it just sat a little further out of the cylinder. I have been searching articles by both men but haven't found it yet.

Has anyone had this done or recall the article?

I alo posted this under the Revolver section of the forum.

Pearce mentioned it in an article in handloader magazine:

http://buffalobore.net/HandloaderDecJan2012.pdf

arfmel said:

Pearce mentioned it in an article in handloader magazine:

http://buffalobore.net/HandloaderDecJan2012.pdf

Click to expand...

Thanks arfmel. I did find one other article with the same mention of it. But I thought the one I saw went into more detail on it.

I guess I am just lost. I bought my NIB Ruger Blackhawk Convertible 7 1/2 inch barrel in 45LC & 45ACP 3 screw in 1971. And it is without dought my favorite SA Ruger and I am lucky enough to own several of them mostly in 45LC`s. I keep hearing ever once in a while about people wanting to shoot 45 Auto Rim ammo thru their 45 ACP cylinder and having them altered to do so. All tho I never tried it or ever really wanted to. I alway thought that I would be able shoot 45 Auto Rims thru my 45LC Cylinder being that they had a rimmed case. Am I wrong on this. And also I have never known anyone with enough 45 Auto Rim ammo to even really bother with this idea. I am sorry and I guess I am just really simple minded on this subject. But I really have enjoyed this Forum, and have learned alot from You Guys & Gals. Thanks for letting me join You.
ken

The rim on a .45 auto rim cartridge is thicker than the rim on a .45 Colt cartridge so they will not fit without altering the cylinder. .45 Cowboy Special brass is the same length as .45 ACP / .45 AR but has the same rim thickness as .45 Colt brass and is readily available from StarLine.

Thank You all for your suggestions and insight.

I had a friend with a lathe modify my .45 ACP cylinder so that I can use .45 Auto Rim. I can also use .45 ACP in full moon clips, if I want to remove the cylinder every six shots.

Starline makes a 45 Special case that I hear can be used normally in the 45 acp cylinder.

The least intrusive way to modify the cyl is by just recessing the chambers for the .020" thicker rim of the 45 AR.

The least intrusive way to use 45 ACP with clips is to start with the metal clips, .040" thick. Take them to a machinist with a Surface Grinder and have them ground to .020". They'll work fine with no modification to the cyl; even easier to load and unload the clips.

I guess I am just lost. I bought my NIB Ruger Blackhawk Convertible 7 1/2 inch barrel in 45LC & 45ACP 3 screw in 1971. And it is without dought my favorite SA Ruger and I am lucky enough to own several of them mostly in 45LC`s. I keep hearing ever once in a while about people wanting to shoot 45 Auto Rim ammo thru their 45 ACP cylinder and having them altered to do so. All tho I never tried it or ever really wanted to. I alway thought that I would be able shoot 45 Auto Rims thru my 45LC Cylinder being that they had a rimmed case. Am I wrong on this. And also I have never known anyone with enough 45 Auto Rim ammo to even really bother with this idea. I am sorry and I guess I am just really simple minded on this subject. But I really have enjoyed this Forum, and have learned alot from You Guys & Gals. Thanks for letting me join You.
ken
Sometimes the 45 auto cylinder can, for whatever reason, be more accurate, or one may want to have milder loads to shoot without all of the extra case capacity of the 45 colt case. Having the cylinder turned at the rear to allow 45 auto rim ammo to function lets one take advantage of a shorter case that is now readily available from Starline. This also allows a roll crimp to be used and still allow the case to headspace on the rim, and the alteration still allows use of regular 45 auto cartridges. However, now that the 45 cowboy special cases are available too, as 10mm mentioned, the point may be moot unless one has plenty of the 45 auto rim cases to use. Also, in a survival situation, it would give a person one more option in ammunition.

The .45 Auto Rim cartridge has an extremely thick rim, much thicker than a .45 Colt rim. The reason for the thick rim is to equal the thickness of a .45 ACP with moon clips. The AR round was introduced after WW I for those folks that had 1917 revolvers and didn't like using the half moon clips. One other advantage is that the Auto Rim cartridge is loaded to lower pressures that the .45 ACP. This makes it a better round to use in .455 S&Ws that have been converted to .45 ACP/Auto Rim. The .455 chambered S&Ws are NOT heated treated while the 1917s were heat treated per the US Gov't. The pressures of a .45 ACP round are about equal to a PROOF load for a .455.

The .45 Auto Rim is also a better round to use in the Webley & Scott .455s that have been re-chambered to .45 ACP/Auto Rim for the same reason-excessive pressure.

slugflinger said:

I alway thought that I would be able shoot 45 Auto Rims thru my 45LC Cylinder being that they had a rimmed case. Am I wrong on this. alteration still allows use of regular 45 auto cartridges.

Click to expand...

Since the Ruger single action is not designed for use with moon clips, their ACP cylinders are machined with normal headspace just like the 45 Colt cyl. Therefore there's not enough headspace for moon clips or the thicker 45 AR rims.

That's why in my post above I indicated the moon clips must be thinned to .020" for use in a Ruger ACP cyl that has not been modified. And why 45 AR still cannot be used.

Yes, alteration still allows use of regular 45 auto cartridges with or w/o clips.

To what end? So you can shoot 45 ACP in a gun you can already shoot 45 ACP in, but with the convenience of having to pull the cylinder out to reload? I don't get it.

But then I don't get why you'd want to shoot 45 Auto rim in your Blackhawk either, unless you happen to load tons of auto rim ammo, but don't want to load 45 ACP or 45 Colt? I'd bet that people who fit that description are rather few and far between.

cas,

The "end" is discussion and understanding. It's not a matter of wanting to do it.

Just FYI: the fastest reload of a SA is swapping a cyl of fired cases for a back up cyl. loaded with moon clipped ammo.