Resizing .45 ACP with .45 Colt die?

TruthTellers

New member
Given all the available .45 ACP brass I can get at the range I'm thinking it's a sign to get dies to load the .45 ACP. I only have one gun right now that can shoot it tho and it's my Ruger Redhawk. So, since this is a revolver only proposition right now, is there anything wrong with using the .45 Colt sizing die on .45 ACP? My thinking is if it works, I don't have to buy a .45 ACP sizer die, but also the ACP case would be completely straight and have no taper at all to it, which might help is shoot better in the Redhawk given its chambers are meant for .45 Colt.
 
Am I to understand correctly that you want to use .45 ACP brass in a .45 Colt cylinder, and not a separate cylinder designed for .45 ACP? If so, it ain't gonna work. With no rim on the case and nothing in the cylinder to prevent forward movement of the case, the cases would either fall too far into the cylinder while loading them, or do so when the firing pin hits the primer. Also, even if it did work, how are you going to seat the bullet and crimp the case? Spend the coin for some more .45 Colt brass.

Don
 
The Ruger Redhawk came in 45Colt/45ACP calibers.
The revolver used a full moon clips, the cylinder is cut
for the full moon clip Colt and 45 ACP interchangeably.
 
Ah, I see now that the Redhawk has a recessed cylinder to allow the use of moon clips. Still, since the throat is WAY out there for .45 Colt rounds, I suspect you will get better accuracy with the longer .45 Colt case. Also, at the very least, you will need a .45 ACP seating die since there is no way of getting the .45 ACP brass up far enough into the .45 Colt seating die for the bullet seating/crimp functions.

Don
 
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If the colt sizing die makes the 45 Auto case narrow enough to hang onto a bullet, there is no reason I know of that you can't resize with it. The 45 Auto dies in carbide are straight side sizers, too. Just be aware the expander and seating dies for 45 Colt may not have enough adjustment range to work with 45 Auto.
 
In the dual-purpose Redhawk, you should be okay. .45 Colt case diameter is .480, and .45 Auto tapers from .476 to .473. For lead bullets, the minimum bullet diameter for both is .450, so that's a wash.

But if you ever get a semi-auto in .45 ACP, you'll probably find that cases sized to .480 won't chamber. The .45 Auto chamber tapers from .4796 to .4720 at the case mouth location.
 
I have resized .45AR cases with s .45 Colt resizer. Just be sure the case will have sufficient neck tension.
 
In the dual-purpose Redhawk, you should be okay. .45 Colt case diameter is .480, and .45 Auto tapers from .476 to .473. For lead bullets, the minimum bullet diameter for both is .450, so that's a wash.

But if you ever get a semi-auto in .45 ACP, you'll probably find that cases sized to .480 won't chamber. The .45 Auto chamber tapers from .4796 to .4720 at the case mouth location.
That's what I figured, but I don't have a .45 semi auto, so it's not a concern for me right now. The day I do get a semi auto .45, I'll buy a .45 ACP resizing die.

I'm thinking that eliminating all taper to the .45 ACP case could help add velocity and possibly accuracy because a significant amount of energy is being used to expand the brass to the .45 Colt chamber.
 
The 0.480" measurement is a SAAMI maximum diameter for a loaded cartridge (with a bullet under the brass) with a tolerance of -0.008, so you would figure the average loaded cartridge to be 0.476" with a bullet in place. Note also that the SAAMI spec allows for use of the old 45 Colt bullet diameter. Now that 45 Colt has been narrowed 0.003", you could expect that, unless the neck wall is significantly thicker than the 45 Auto cases have, the sizing die will probably be designed for the narrower bullet and may not be at all far off with the 45 Auto case. This is why I said, "if" it makes the case narrow enough. I think it well may because I don't think the brass makers have thickened their brass for the smaller diameter bullets. They want it to work with both bullet sized.

I would simply suggest trying it on a couple of range foundlings and see if you can't push a 0.451" past the case mouth by hand, it is probably going to work.
 
I do the opposite. I do not have 45 colt dies, to I use ACP dies. Works fine.

Yep, the opposite will work, since you can raise the die up higher in the press to account for the longer length of the .45 Colt brass.

Don
 
.898" vs 1.285" .473" vs .480"

My concern isn't so much the length, most dies will allow the expander and seating stems to adjust for that approx. 1/3" difference in length. My concern is are dies made to size to .480" going to size the smaller ACP case ENOUGH for proper bullet fit? They are made to size to slightly under the .480" spec but is it going to be enough for the ACP? What about "stacking tolerances"?

I can see a situation where your .45 Colt die might size SOME acp brass enough, but not all acp brass. And, there is one thing you can't do, crimp ACP brass in a .45 Colt die.

Guess you'll just have to try it and see.

Or, you could spend a few bucks ONCE, and get dies made for the job you want then to do, and not worry about it.
 
berettaprofessor said:
Lordy, just buy the 45ACP dies....Lee 3-die set is $33...
That brings up an interesting question:

The .45 Automatic Colt Pistol cartridge is (:duh) intended for use in a semi-auto pistol, in a chamber where the cartridge headspaces on the mouth of the case. For that we want a taper crimp, and .45 ACP dies are typically made to produce a taper crimp.

But, Mr. TruthTellers wants to shoot .45 ACP out of a revolver. Maybe he won't have a problem with recoil backing the bullets out of the case, but maybe he will. He's not going to be worried about headspacing on the case mouth, so a roll crimp would be the better choice.

Does anyone make a roll crimp die for .45 ACP? If so, is it a good idea or a dumb idea to make up some roll crimped, revolver-only .45 ACP?
 
I never said that I was going to use .45 Colt flaring, seating, or crimping dies on these .45 ACP handloads, I said just resizing.

I figure the Colt dies I have are too long to flare the short ACP case and the seater I would rather use one for ACP since it will have the taper crimp.
 
A couple of things to consider,

first is the amount of "pull" you get firing .45ACP loads from a heavy gun such as the Redhawk. The usual ACP taper crimp will almost certainly be enough.

How much crimp you need depends on the amount of bullet pull during recoil, and that varies with how much recoil the load produces, and that varies with the weight of the revolver.

For example, I have done a little experimenting and discovered that there are .38 Special loads that I can shoot uncrimped in a S&W M28 without any bullet jump, and the same ammo in a Model 19 the bullets edge forward slightly.

Bigger bores's heavier bullets change the situation slightly, in detail, but the same principle seems to hold true. I'm not talking magnum level recoil here, I'm talking the relatively mild recoil of the .45acp in a magnum "heavy" revolver.

I shoot ACP from a Ruger Blackhawk, and the recoil is "light" compared to my .45 Colt loads. In the heavier Redhawk, the recoil would be even less, so the force "yanking" the case off the bullet would be less, and I expect within the ACP's taper crimp's ability to handle.

Second, there were ACP seating dies that applied a roll crimp. You need to look at die sets made back in the 70s or earlier, but they used to come that way, for use with the .45 Auto Rim.

ACP cases CAN be roll crimped and still work in some semi autos. You just "kiss" the case with the crimp shoulder in the die. It's not much, but its enough to remove the flare and keep the bullet where it should be during feeding. Keep in mind that this was done back when the Colt Govt model was the only .45ACP semi auto common.

If the regular taper crimp works to keep the slugs in place in your revolver, there is no point to roll crimping the ACP.
It's simple enough to check. Check round #6 in the cylinder for length (baseline) then just shoot 5 rounds, and check it again. If they bullet didn't move, you're good. If it does move, then you have to decide whether to apply a little more crimp and retest, or if you can live with it. If it has "jumped" only a small amount, that's one thing, if its almost out of the cylinder that's something else.

IF, for some reason you need to apply a solid roll crimp to a .45acp (and you are using a bullet made for that, something you can do in revolvers), there is a way. Find a used .45 Colt seater die (roll crimp), take it to your local machinist and have them cut the bottom off, enough so the acp case reaches the crimp shoulder.
 
Does anyone make a roll crimp die for .45 ACP? If so, is it a good idea or a dumb idea to make up some roll crimped, revolver-only .45 ACP?

Yes, RCBS makes it and I bought and use it. I load the .45 Cowboy Special case which is basically a .45 ACP case with a .45 Colt rim on it. I also load the .45 AR case, and in a revolver, if it don't have a roll crimp in a crimp groove, it just don't look right.:)

Don
 
That's what I figured, but I don't have a .45 semi auto, so it's not a concern for me right now. The day I do get a semi auto .45, I'll buy a .45 ACP resizing die.

I'm thinking that eliminating all taper to the .45 ACP case could help add velocity and possibly accuracy because a significant amount of energy is being used to expand the brass to the .45 Colt chamber.
How will you seat and crimp the bullet ... can a 45 Colt seat/crimp die be adjusted to seat and crimp the bullet ?
The 45 acp is mighty short compared to the 45 Colt .
Gary
 
How will you seat and crimp the bullet ... can a 45 Colt seat/crimp die be adjusted to seat and crimp the bullet ?
The 45 acp is mighty short compared to the 45 Colt .
Gary
I was going to buy the seating/crimping die. The mouth flare I was going to try tonight and see if the Colt die will work on the ACP case.
 
The mouth flare I was going to try tonight and see if the Colt die will work on the ACP case.

If you have your expander die set for .45 Colt, and have 1/2" or more of stem sticking out the top of your die, it will have enough adjustment to work on .45ACP.

Same goes for the bullet seating stem.

However, the shellholder will contact the bottom of the .45 Colt seater die before the ACP case reaches the crimp shoulder inside the die.

You can "sort of" size an ACP case in a .45 Colt sizer die. I haven't tried it (no need) and I wonder how well a die made to size a case to .480" will work on a case that's supposed to be .473" at the mouth.

If your stems have enough adjustment (and most do) you can flare an ACP case in a .45Colt die, and you can seat a bullet in an ACP case in a .45 Colt die, but you cannot crimp an .898" case in a die made to crimp a 1.285" case, unless you cut the bottom of the die off, to allow it.

I'm not doing that, sorry...

Besides, check the cost of your local machinists, it might be cheaper to just buy a .45 ACP crimp die. Might even be cheaper to buy a whole ACP set...
 
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