45 ACP bullet seating and tamper crimp

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stodd

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Hello,

After reading both of my reloading manuals I have a question. I'm using the carbide 3 die set for the 45 acp from RCBS. Having and issue with getting the tamper crimp correct. Would it be better to just seat the bullet with the RCBS seater die and then get a separate tamper crimp die?
 
You can seat and crimp in two separate steps if you want with the die you have. I taper crimp with a separate die. (I used to seat and crimp in two steps with one die) All you want the taper crimp to do is remove the flare, that's all. It will not hold the bullet in place. Do this test - seat a bullet (with no crimp at all) and press the round against the edge of your bench (pretty hard). If the bullet is moved deeper into the case then your expander die is too large in dia. for that bullet and is over-expanding the case mouth. You can remove the expander button and turn it down in a drill with sandpaper until it is 3 to 4 thous. smaller than the bullet dia. Then apply just enough crimp to remove the flare. Case neck tension is the key to preventing bullet setback. A lot of die manufacturers produce expander dies that are oversized. You can also measure a bullet and then measure your expander plug and see what the difference is. Bullet setback in a .45 ACP is not really very dangerous as the pressure is pretty low but you still want to have good case neck tension on the bullet. With a modern high pressure round like a .40, 10mm or .38 Super a little setback can blow a gun.
 
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So I've setup 38 spl and 9mm rcbs carbide dies in the past about 4 years ago. But for some reason i'm having a hell of a time getting these new 45 acp rcbs dies setup correct on the bullet seater/tamper crimp die. Anyone have some info on the easy way to setup the seater/crimp die? I didn't get the rcbs instructions in the dies for some reason and can't remember the steps on how I setup my 38 spl and 9mm years ago.

Thanks..
 
Back out the die, screw in the seater stem.

Seat.

Back out the seater stem, screw in the die.

Crimp.

Screw in the seater stem.
 
Having and issue with getting the tamper crimp correct.
You could be over crimping ?
Case mouth should measure .470-.473" with the bullet seated.
I have seated and crimped in separate steps with thick brass and HP bullets, but I mostly seat and crimp in one step with RCBS dies for 45 acp.
 
You don't need much crimp. Just enough to take the flare out. If the loaded round drops freely into the chamber, you have enough crimp.
 
Im definately not one to argue about terminology, but its a taper crimp, not a tamper crimp. And, like the above posters said, straighten out the flare and you are good to go!
 
Thanks for this thread, I've been gearing up to reload 45acp and every bit of information shared on this subject is greatly appreciated.
 
I found that buying and using a separate taper crimp die saves time and adjustment time. I just bought a RCBS taper crimp die and use it as a fourth step.

I dust the bullet/case with mica or talc powder and taper crimp. Look for about 1/8" of crimp and your set.
 
Adjust the die body down over the case until you feel the crimp ledge hit the case, then adjust the die body up so there is no contact. Then set the die ring and screw the seater stem up or down to get your targeted OAL. 1.265 in this case. As always, there will be a little variance. I try for OALs that fall in between 1.260 and 1.265 with a RN in .45 ACP.

Then when you have the seater stem real close, adjust the stem way up out of the way and then adjust the die body down a hair at a time until you have the crimp you need. Just remove the bell or a hair more. Too many people over crimp auto calibers. Remember, case lengths vary, so you want the die to remove the bell entirely on the short cases, while the longer cases will get a slight inward crimp. .001 or maybe a hair more.

Lock the ring down and turn the seater stem down to touch the top of the bullet in the loaded round. Then turn the stem down 1/8 turn more.

Then seat/crimp a bullet and see what you have. If it falls in range, and the crimp is OK, try another, and another. If you get through several and everything is OK, your done. If not, tweak a hair to adjust the crimp or seating depth, remembering that they affect each other. If the crimp is good and you only have to adjust the seating depth a little it's easy. If you have to adjust the crimp a little by moving the die body, you will have to readjust the seater stem as well.

The case head should be at least flush, to under the barrel hood. Headspace is determined by the chamber and the case length. Don't worry about it. We are just looking for a seating depth that does not interfere with chambering.

The "plunk" test. http://www.thehighroad.org/showthread.php?t=506678


attachment.php
 
For rimless AL cartridges, once you've got your desired OAL, the crimp involves nothing more than removing the bell. Simply adjust the entire die down until it is just removing the bell, no more than that, or you will begin losing neck tension, possible head space issues that can cause mouth pinching in the throat, among other undesirable issues, and deforming the bullets too.

You shouldn't be having an issue as long as you are only using the crimp as a means of removing the mouth belling. Rimless cases head space on the mouth, so over crimping, or actually producing a crimp per say, is the wrong approach. In other words, rimless cartridges do not attain their neck tension from the crimping step at all. This is where many reloaders become confused about the purpose of the crimp on a rimless cartridge.

Rimmed cases are a whole different story, and they do actually utilize a functional crimp for the purpose of bullet hold, or neck tension.

GS
 
A lot of answers on how much to crimp the .45 ACP. Most are right, but;

I always tell new reloaders to forget the term "crimp" when talking/working with semi-auto cartridges. No "crimp" is needed. The case mouth is straightened, removing any flare with a taper crimp die. That's it. Talking about "crimping" a 45 ACP often adds confusion, with a new reloader actually looking for some case deformation from a taper crimp die. No need to try and hold the bullet tighter in the case as neck tension is sufficient.

To answer your question about separate dies; if using a turret or multi die set-up, yes get a dedicated taper crimp die. If using a single stage press, use the die adjustment/crimping procedure posted above (seat all, readjust dies for mouth straightening and process ["crimp"] all...)
 
You really are not crimping at all unless you use a bullets with a cannelure. You are simply taking the flare back out of the case and this makes the bullet firm against the case wall.The brass is much softer than the bullet,that is why you can only truly crimp against a cannelure .Alot of people mistakenly think they can crimp a bullet without a cannelure , thus the problems are then created.
 
You can seat/crimp in one operation, but it's a nail-biter.
Recommend you get a separate taper-crimp seater die and just remove the seating stem.

In the end (as noted by WALKALONG above) you want to end up with a mouth diameter
as shown below -- no matter what the bullet design.

2j0iopc.jpg
 
When I first started loading 45 Auto I was loading for my then new Blackhawk convertible. I loaded up my first batch of ammo using RCBS dies and new Starline brass on my Rockchucker, crimping in a separate step with the seating stem removed, before I even had the gun. It was backordered. When I finally got it I found that a couple of the chambers were slightly tighter than the others and wouldn't chamber my handloads. They would chamber factory ammo though. I ran out and bought a Lee Factory Crimp die and ran them all through it and problem solved. I've since purchased Lee crimp dies for every handgun cartridge I load. I use RCBS three die sets for everything except the crimp. Not having to remove the seating stem and then readjust the seating/crimping die every time is worth it alone too though. I've never had good luck seating and crimping at the same time. A four die set works best for me.
 
You really are not crimping at all unless you use a bullets with a cannelure. You are simply taking the flare back out of the case and this makes the bullet firm against the case wall.The brass is much softer than the bullet,that is why you can only truly crimp against a cannelure .Alot of people mistakenly think they can crimp a bullet without a cannelure , thus the problems are then created.
Sorta, maybe, not really. Unless you're talking about a roll crimp, where case material is formed/"rolled" into the sides of a bullet, a cannalure isn't the deciding factor in crimping a bullet. I have "crimped" thousands of plain sided, no cannalure bullets (mostly for my semi-autos).

Removing the flare (with a taper crimp die) is only straightening the brass, no added bullet/neck tension ("firm against the case wall").

None of the bullets I have ever reloaded are harder than the brass cases holding them (I haven't tried any brass solids, yet). The cases are thin and malleable, but not softer. I'm reloading for my 1911 a lot lately and perhaps the last 1,200 or so bullets without a cannalure were processed wrong?

Roll crimping is for bullets with a cannalure or crimp groove. Taper crimping is for straight sided bullets w/o a groove or cannalure. But, with experience, a knowledgeable reloader can use either...
 
Jacketed bullets seat and crimp well in one step....lead not so well. With my RCBS dies, I seat and crimp .45ACP in one step and have no problem. For crimping .45ACP, after I get my bullet seated to the correct depth, I back off the seating stem with the case left in the upright position, I then loosen the lock nut and turn the die down by HAND until I can't turn it anymore. I then tighten the lock nut and then turn the seating stem down till it contacts the bullet. I then lower the case and turn the seating stem down just ever so little(maybe a tenth of a turn) and then tighten it's lock nut. Seems if I don't make that little extra turn down my OAL goes up above the intended length. Works for me everytime.
 
I had a lot of trouble with my cast bullets and my 1911s.
I was using a Lee 225 grain Round nose tumble lube mold.
Sized .452 thru a lee sizer.
The cast bullets sized to .452 and loaded with RCBS dies loaded and ran just great in the Ruger P345 and the hi-point .45 and the hi-point .45 carbine.
Same bullet would not go into any of the 3 1911s I would up trying them in.
They just would not chamber

I tried a Lyman mould - slightly better results
I tried a Lee factory crimp die - slightly better results
I bought a Lee .451 sizer.

That + the factory crimp die works. The same bullets shoot fine in everything.

lesson: some guns are a lot pickier about what you feed them.
 
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