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Michael J. Spangler
07-19-2012, 09:22 AM
hey everyone

do you taper crimp or roll crimp?

if you roll crimp what die do you use? all i have is a lee 4 die set for 45 acp right now. i don't think these can roll crimp.

i know they sell a die that can taper or roll crimp but i don't think this was the set that does that.

thank in advance!

Iron Mike Golf
07-19-2012, 11:10 AM
45 ACP headspaces on the case mouth (assuming you are not shooting a revolver using moon clips). When you headspace on the mouth, you need a taper crimp.

captaint
07-19-2012, 11:17 AM
When I loaded my 45AR's, I did not roll crimp them. Haven't fired them yet, so I can't say how they'll shoot. However, being they are rimmed, there's no reason we could not roll crimp them. I just used my reg 45ACP dies, so...... enjoy Mike
There is one thing. Probably don't have a "crimp groove" in most ACP type boolits. You could still crimp just above the top band.

Iron Mike Golf
07-19-2012, 11:25 AM
Oops. I didn't get that AR was Auto Rimmed. My bad.

theperfessor
07-19-2012, 11:35 AM
I bought the RCBS roll crimp die as an extra item to supplement my standard RCBS .45 ACP die set which comes with a taper crimp die. I use it (lightly) for heavier bullets (250+ grs) that have a crimp groove. I use a taper crimp for 200/230 gr bullets, but even then its just enough to straighten out the necks. I use a homemade M-die that gives the proper neck tension so there isn't any real flare to turn back in.

Char-Gar
07-19-2012, 11:50 AM
I have fired lots of AR and ACP with clips in sixguns over the years. If the bullet has a crimp groove (like a Keith type bullet) I roll crimp into crimp groove. My RCBS seating die does that just fine. If there is no crimp groove, I use a taper crimp die and taper crimp.

My RCBS die set does the roll crimp and I had to buy an extra taper crimp die. My dies are at least 25 years old.

runfiverun
07-19-2012, 12:43 PM
heck i give a bump in the roll crimp for one of my 1911's.
in my 625 with the ar cases i just taper crimp, unless i am using one of the heavy [250+] boolits.

Michael J. Spangler
07-19-2012, 02:18 PM
Sorry I should have mentioned I planned on using this with heavy 45 colt boolits.

runfiverun
07-20-2012, 12:24 AM
treat it like a short schofield or colt round then.

MikeS
07-20-2012, 02:33 AM
You mentioned that you have Lee dies, they're sold as being for both 45ACP and 45AR, and using the boolit seating die, they WILL do a roll crimp. I have a set of Lyman dies as well, and the Lyman dies seem to only do a taper crimp. When loading 45AR I use my normal die setup (mostly the Lyman set, but with a Hornady taper crimp die as well), but I replace the taper crimp die with the Lee seating die adjusted to give the cases a nice roll crimp. When using the Lee die as a crimper I remove the boolit seating part, along with the screw adjuster.

I believe the Lee 4 die set also includes the Carbide Factory Crimp Die, if so, don't bother using it (for loading AR or ACP) when loading lead boolits, as it can cause the boolit to get sized down smaller than it should.

When I loaded the AR cartridges I used a 238gr SWC that has a nice crimp groove (the 452423 the boolit Keith designed specifically for the 45AR), and gave them a moderate roll crimp, I used Blue Dot powder. When I loaded some 45ACP rounds with a 230gr boolit and the exact same charge of Blue Dot I got lots of extra unburned powder coming out of the muzzle, in the gun, etc. and the load had much less recoil than a 'standard' load of around 5gr of Bullseye. When I shot the 45AR rounds with basically an identical load (there might have been a difference between the 2 boolits of maybe 5gr or so) they had about the same recoil as the 'standard' Bullseye load, and there wasn't any unburned powder! I can only assume that the crimp was the difference, the roll crimp holding the boolit in tighter than the taper crimp I normally use, allowing the powder to burn fully.

Michael J. Spangler
07-20-2012, 08:35 AM
thats very interesting. i'll have to mess with the lee dies to see if they roll cramp or not.
have their dies always roll crimped or is that something new?

tonyjones
07-20-2012, 04:48 PM
If your existing dies will not roll crimp try a Redding Profile Crimp Die. Use your existing die to seat but not crimp and the PCD to complete things.

Regards,

Tony

MikeS
07-21-2012, 12:12 AM
thats very interesting. i'll have to mess with the lee dies to see if they roll cramp or not.
have their dies always roll crimped or is that something new?

I'm not really sure. I know that while their dies will roll crimp, if you back off the die a little they will also do a taper crimp. In fact, if you look at Lee's info about their taper crimp dies (not the FCD) it basically says that with newer Lee dies (they mention a date, but I don't recall what it is) that they're not needed (the taper crimp dies) as they do the same taper crimp. Of course if using a progressive press, or even just a turret press it's nice to crimp in a separate operation, so having a separate taper crimp die still comes in handy even with the newer Lee dies. Lately I've been loading 45ACP without using any 45ACP dies! I've started sizing using a 45 Colt sizing die as it sizes the cases about .002 larger in diameter than ACP dies, and when loading a flat point boolit I use a 45 Colt seating die for it's flat seating stem.

Michael J. Spangler
07-21-2012, 10:55 AM
good idea.

looks like i'm going to need a taper crimp insert a 45 colt taper crimp die to get it done right.

i'm going to try to load some with a taper crimp and see how they shoot. i'm sure they'll be fine as long as they're not too hot.

Fixxah
07-21-2012, 07:03 PM
hey everyone

do you taper crimp or roll crimp?

if you roll crimp what die do you use? all i have is a lee 4 die set for 45 acp right now. i don't think these can roll crimp.

i know they sell a die that can taper or roll crimp but i don't think this was the set that does that.

thank in advance!


Dude, slight taper ONLY!

Michael J. Spangler
07-21-2012, 07:27 PM
Just loaded some 255s with a light taper crimp. Let's see how they go.

35remington
07-22-2012, 01:37 PM
A light taper crimp does nothing to hold the bullet in place.

Want to see for yourself? Take an unsized case, hold the bullet at the right level with a tuft of dacron, and taper crimp it. This will show the effect of the crimp alone.

Knock the nose of the crimped powderless cartridge against a bench. Not only does it fall into the case when lightly tapped nose first against a bench, it comes out easily as well.

As I said.....a light taper crimp does nothing to hold a bullet in place.

Maximum protection against bullet pull, which is what you want in a revolver, is obtained with a roll crimp.

Michael J. Spangler
07-22-2012, 03:29 PM
That's true about the taper crimp. Alone it does nothing
Just like in rifles
The crimp helps with setback but neck tension holds it in place. Which is a function of sizing

In the .45 on the dillon 550 the powder funnel expander does that.

I'm going to start light and mess around while I'm waiting on the roll crimp to come in.

I'm sure it's only needed for the heavy loads.

felix
07-22-2012, 03:45 PM
Using a roll crimp die, when set-up like a taper crimp die, with a case having 0.002 compression on the boolit from the sizing die, and rolling the case edge into a boolit on its bearing surface, will give the best boolit "holding" power by far. The only way to get the boolit out SAFELY is to shoot it out or drill a hole in it and pull it out using a coat hanger wire through the hole. ... felix