.45 ACP/.45 Colt convertible revolver
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CraigC
Sixgun Nut
Because there's a lot bigger difference between the .45ACP and the Colt than there is the .44Spl and Magnum. It's more than twice the difference, .169" versus .387". Or slightly greater than that of the .32S&W Long versus .327Federal. Not to mention virtually all .45Colt chambers are oversized, except USFA, Freedom Arms and the BFR. Which leaves a lot of wiggle room for the bullet. It's enough to make a difference. In the .38/.357 or .44's, the bullet has reached the throat before it clears the case. Versus basically freebore when .45ACP is fired in a .45Colt chamber.
tbob38
Member
Not in my guns. Just checked a Smith 27 with 2 bullets. With bullet in the forcing cone, one leaves 1.355" to the recoil plate, the other 1.331". A random new case is 1.144". The bullet leaves the case before it enters the throat.
tbob38
Member
That sure looks like the best way to do a convertible DA revolver, by far.
Food for thought.
This is a 1916 vintage 455 HE MkII that has been modified just a wee bit. It now has a chopped 45 ACP barrel (.452), a post war 45 ACP cylinder bored out to take 45 Colt cartridges. This enables the use of
45ACP in moon clips, 45AutoRim, .45 Colt, and .45 Winchester Mag brass, loaded to old Colt 45 pressures & velocities, in moon clips. All of those fire .452 caliber bullets these days. The gun will fire the other rounds but there is free bore with the ACP and AR cases.
My favorite is the .45 "win mag brass". .45 Win mag brass is merely 45ACP brass stretched to 45 Colt length. Thus I can use .45 Colt like ammo with moon clips which put front of the bullet at the end of the cylinder and a fraction of an inch from the forcing cone. There is no free bore or bullet jump to reach the forcing cone.
This old rascal puts them right where I point the gun..The gun does it's part if I do mine. With all of those big holes in this gun, it is surprisingly easy to carry every day.
This is a 1916 vintage 455 HE MkII that has been modified just a wee bit. It now has a chopped 45 ACP barrel (.452), a post war 45 ACP cylinder bored out to take 45 Colt cartridges. This enables the use of
45ACP in moon clips, 45AutoRim, .45 Colt, and .45 Winchester Mag brass, loaded to old Colt 45 pressures & velocities, in moon clips. All of those fire .452 caliber bullets these days. The gun will fire the other rounds but there is free bore with the ACP and AR cases.
My favorite is the .45 "win mag brass". .45 Win mag brass is merely 45ACP brass stretched to 45 Colt length. Thus I can use .45 Colt like ammo with moon clips which put front of the bullet at the end of the cylinder and a fraction of an inch from the forcing cone. There is no free bore or bullet jump to reach the forcing cone.
This old rascal puts them right where I point the gun..The gun does it's part if I do mine. With all of those big holes in this gun, it is surprisingly easy to carry every day.
CraigC
Sixgun Nut
Not talking about the forcing cone but the chamber throat.
tbob38
Member
Ok. Just checked a Ruger New Vaquero and a 45 ACP bullet is just touching the chamber throat as it leaves the cartridge case.
This should not be hard to understand.
The bullet will be very close to the chamber throat constriction in a dedicated ACP cylinder.
A .45 Colt bullet will be close to the chamber throat constriction in a .45 Colt cylinder.
The goal is to reduce as much uncontrolled bullet jump as possible, keeping the bullet in as straight a line as possible.
The distance between bullet nose and chamber throat will vary slightly, depending on bullet & COAL in both calibers, in dedicated cylinders.
If you just set a standard 230 ACP round base up next to an average 250-ish grain .45 Colt load, you can see there's much more difference in COAL between those two than you'll find in your average 158 grain .38 Special & 158 grain .357 COAL.
There's a lot more freebore bullet jump from a .45 ACP bullet in a chamber cut for .45 Colt.
This affects accuracy negatively in many ACP loads, when the ACP bullets have room to yaw & not strike the chamber throat constriction squarely.
This is not like the .38 in a .357 or a .44 Special in a .44 Magnum.
It's a phenomenon that does occur in this convertible Red.
As I said, I documented it in two different test sample guns, using the exact same ammo in both & under the same 25-yard testing protocols.
And, 6 or 8 years back, I tested a custom Super Red converted to fire .454, .45 Colt, and .45 ACP through the same modified cylinder.
Accuracy with the ACP was virtually worthless in that gun, and velocities were also lowered markedly, too.
It's real, it happens.
Shooting ACPs through the convertible Red simply causes a reduction in accuracy with many loads.
It's nowhere near as uniformly accurate as the convertible Blackhawk's ACP cylinder.
I happen to have one of those.
I'm not here, and I haven't anywhere else, been trying to tell anybody not to buy the convertible Red.
I just try to educate people talking about buying one intending to use it as primarily an ACP revolver.
It's a .45 Colt gun that also happens to take ACPs on the side, but not as well.
Denis
The bullet will be very close to the chamber throat constriction in a dedicated ACP cylinder.
A .45 Colt bullet will be close to the chamber throat constriction in a .45 Colt cylinder.
The goal is to reduce as much uncontrolled bullet jump as possible, keeping the bullet in as straight a line as possible.
The distance between bullet nose and chamber throat will vary slightly, depending on bullet & COAL in both calibers, in dedicated cylinders.
If you just set a standard 230 ACP round base up next to an average 250-ish grain .45 Colt load, you can see there's much more difference in COAL between those two than you'll find in your average 158 grain .38 Special & 158 grain .357 COAL.
There's a lot more freebore bullet jump from a .45 ACP bullet in a chamber cut for .45 Colt.
This affects accuracy negatively in many ACP loads, when the ACP bullets have room to yaw & not strike the chamber throat constriction squarely.
This is not like the .38 in a .357 or a .44 Special in a .44 Magnum.
It's a phenomenon that does occur in this convertible Red.
As I said, I documented it in two different test sample guns, using the exact same ammo in both & under the same 25-yard testing protocols.
And, 6 or 8 years back, I tested a custom Super Red converted to fire .454, .45 Colt, and .45 ACP through the same modified cylinder.
Accuracy with the ACP was virtually worthless in that gun, and velocities were also lowered markedly, too.
It's real, it happens.
Shooting ACPs through the convertible Red simply causes a reduction in accuracy with many loads.
It's nowhere near as uniformly accurate as the convertible Blackhawk's ACP cylinder.
I happen to have one of those.
I'm not here, and I haven't anywhere else, been trying to tell anybody not to buy the convertible Red.
I just try to educate people talking about buying one intending to use it as primarily an ACP revolver.
It's a .45 Colt gun that also happens to take ACPs on the side, but not as well.
Denis
tbob38
Member
This should not be hard to understand.
The bullet will be very close to the chamber throat constriction in a dedicated ACP cylinder.
A .45 Colt bullet will be close to the chamber throat constriction in a .45 Colt cylinder.
The goal is to reduce as much uncontrolled bullet jump as possible, keeping the bullet in as straight a line as possible.
The distance between bullet nose and chamber throat will vary slightly, depending on bullet & COAL in both calibers, in dedicated cylinders.
If you just set a standard 230 ACP round base up next to an average 250-ish grain .45 Colt load, you can see there's much more difference in COAL between those two than you'll find in your average 158 grain .38 Special & 158 grain .357 COAL.
There's a lot more freebore bullet jump from a .45 ACP bullet in a chamber cut for .45 Colt.
This affects accuracy negatively in many ACP loads, when the ACP bullets have room to yaw & not strike the chamber throat constriction squarely.
This is not like the .38 in a .357 or a .44 Special in a .44 Magnum.
It's a phenomenon that does occur in this convertible Red.
As I said, I documented it in two different test sample guns, using the exact same ammo in both & under the same 25-yard testing protocols.
And, 6 or 8 years back, I tested a custom Super Red converted to fire .454, .45 Colt, and .45 ACP through the same modified cylinder.
Accuracy with the ACP was virtually worthless in that gun, and velocities were also lowered markedly, too.
It's real, it happens.
Shooting ACPs through the convertible Red simply causes a reduction in accuracy with many loads.
It's nowhere near as uniformly accurate as the convertible Blackhawk's ACP cylinder.
I happen to have one of those.
I'm not here, and I haven't anywhere else, been trying to tell anybody not to buy the convertible Red.
I just try to educate people talking about buying one intending to use it as primarily an ACP revolver.
It's a .45 Colt gun that also happens to take ACPs on the side, but not as well.
Denis
Oh, it's not hard to understand at all. I'm just concerned with accuracy, both in the shooting and in the description of what is going on. I agree that best accuracy is obtained with the best fit of chamber to cartridge.
You say you did the experiments and documented the results. Is this documentation somewhere that we can view? "no where near" and "practically worthless" as descriptions of accuracy aren't nearly as worthwhile as actual data. Did you use a Ransom rest by any chance?
I'm really interested in a 4" Redhawk in 45 Colt. I see them on Gunbroker.com. But the Ruger web site only shows the convertible model. A concern of mine is that to make room for moon clips, more of the case is unsupported. Enough to cause a problem with heavy loads?
mcb
Member
The moonclip cut for 45 ACP removes ~.035 from the face of the cylinder/extractor. That does not even get up the bottom of the primer pocket of a 45 Colt case. It will not hurt your strength or case support at all. As you can see in the image below (not my image) nearly all the material is removed is from the extractor star and very little from the actual cylinder.
tbob38
Member
mcb
Member
My guess is that they simply remove material from the face of the extractor. Most third parties I have seen do moonclip conversion simply machine the cylinder and star as an assembly. If Ruger cuts the pocket in the cylinder deeper for the extractor it would require a special extractor since that would also recess the ratchet pattern and locking pin also, Those features cannot be move down with the extractor or you would have many issues. It would also weaken the cylinder removing more of the web between charge holes deeper into the cylinder.
If you're curious a video of the way TK custom does the moonclip cut on a S&W 686 cylinder:
tbob38
Member
mcb
Member
It appears to have been done on a manual machine with an manually driven index table. The tool appears to be a TiN coated carbide and a revolver's cylinder is not especially hard. No lube should really be needed for how little material is being removed. Though with the way the chips are sticking and the smoke it appears a bit of cutting fluid was placed on the tool/part.
There's a 2 Cylinder 25-2 Shooter (rough finish) on GB right now.
https://www.gunbroker.com/item/764931476
You can find the entire write-up, with 25-yard accuracy results through both revolvers & photos of the gun's features, in the Kindle eBook through Amazon.
It's too lengthy to repeat here.
25-yard groups in ACP ran from 3 inches to 13 inches, depending on the load.
The older write-up some years back on the failed custom Super Red was cancelled.
Accuracy with ACPs through the .454 chambers was so bad, and velocity loss so great, among other problems with the conversion, that there was no point in going ahead with it.
Denis
It's too lengthy to repeat here.
25-yard groups in ACP ran from 3 inches to 13 inches, depending on the load.
The older write-up some years back on the failed custom Super Red was cancelled.
Accuracy with ACPs through the .454 chambers was so bad, and velocity loss so great, among other problems with the conversion, that there was no point in going ahead with it.
Denis
tbob38
Member
tbob38
Member
I'd love to read it but don't know the name of the book. Can help?
tbob38
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