how important is it?


February 3, 2008, 03:34 AM
to have a TAPER CRIMP DIE if your reloading 45ACP for a ruger P90 and a kimber 1911??

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February 3, 2008, 04:48 AM
The taper crimp die is more forgiving of any length variation you may have in the brass you're reloading, whereas the roll crimp isn't. Most of the 45 ACP pistols will be very forgiving of headspace as the extractor will generally prevent the case from going too deep into the chamber.

February 3, 2008, 05:03 AM
well i just need to know if my reloads will feed ok with out it?

February 3, 2008, 06:53 AM
I'm sure they will work fine as long as you adjust the roll crimp to only remove any belling on the casemouth ....and NOT actually roll the casemouth in.

February 3, 2008, 07:50 AM
Take a "finished" round (after just removing the belling) and put it against the edge of your bench with the nose of the bullet on the bench and your thumb on the back of the case. See if you can push the bullet deeper into the case . ..if you can then I'd say you need a taper crimp die. (or you can pick up a Lee FCD for about $9)

Just my .02


The Bushmaster
February 3, 2008, 10:53 AM
If you are loading .45 ACP the seating die that came with your set has a taper crimp. Especially if it is a Lee set (I know because I called Lee to find out quite a while ago). On .45 ACP all you have to do is remove any bell left after seating the bullet. If you must crimp the case mouth be careful not to crimp it too much as you may damage (distort) the bullet and as the .45 ACP headspaces on the case mouth it may set too deep in the chamber for the firing pin to reach it. True...On most .45 ACP pistols (especially those base on the 1911) the extractor holds the case head against the breech face, but I would not trust it to fire every time. I would rather insure that the cartridge headspaced on the case mouth...As it's supposed to...A good measurment at the mouth of a finished .45 ACP is .468 to .472. I just rechecked my loaded rounds and all of them are at .471 to .472......

February 3, 2008, 11:40 AM
Bushmaster: Excellent response. However, 45ACP dies can be either Roll or Taper crimp. You must look on their box to see for sure. Many revolvers are set up to fire 45ACP with half moon clips and therefore need a roll crimp.

Check out the attached headspace illustration:

February 3, 2008, 12:43 PM
Some people who load for use with moon clips in revolvers roll crimp, but they don't need to, they could taper crimp as well if they chose to do so.

Perhaps a roll crimp works better in that app. I don't know. :)

February 3, 2008, 01:16 PM
All standard .45 ACP die sets will do a taper crimp.
Some, like Lee may do both.

Generally, if you want to roll-crimp for a .45 ACP revolver, you need a .45 Auto-Rim seating die, or a Lee FCD for roll crimping revolver.

It would be almost unheard off for any standard .45 ACP seating die to not be able to do a simple taper crimp for use in auto-pistols.

That's what they are made for!

February 3, 2008, 01:39 PM
Taper "crimp" relies on neck tension for bullet retention, and to me is nothing but a bell removal die. Roll crimp actually bites into the bullet adding resistance to bullet movement along with neck tension, and definitely what I would want if shooting a revolver.

I do not use the Lee FCD for pistol ammo, as it destroys the optimal diameter that I want for my cast bullets.

February 3, 2008, 05:56 PM
my dies are hornady, i'm not loading for a revolver, i'm loading 1911 and a ruger P90.

how do i remove the bell?

and would it be ok to just load a round and shoot it? or will my 1100$ kimber blow up?

February 3, 2008, 06:17 PM
Roll crimps are for "rolling" the brass into a crimp groove (which is shaped like a curve, not a even bottomed groove) in a lead bullet or the cannelure of a jacketed bullet. Sometimes it is used to roll over the front edge of 148 grain plated DEWC's. 148 Lead DEWC's usually have a crimp groove. Some folks lightly roll crimp .45 ACP rounds, but mostly people taper crimp all auto rounds. It only needs to be enough to remove the bell or a bit more, depending on your preference. Neck tension does 90% to 99% of the job of holding the bullet and getting good start pressure on auto rounds. The fact that the bullets get into the rifleing right away compared to a revolver also helps start pressures.

February 3, 2008, 06:49 PM
how do i remove the bell?

You should be able to see the belling if you hold the round up, but in the case where you're just barely belling the round it can be a little tougher. I find I can feel it with my fingers. (are you loading cast or jacketed?)

Anyway, what you'll do to remove the bell is to raise the ram to it's highest point with a shell in the shellholder. Screw down the die until you feel it contact the casing. (back the bullet seating stem way out) Drop the ram and turn it another 1/8 - 1/4 turn and then raise the shell back up into the die. It should remove a little bit of the belling. The best thing to do is use your mic or caliper to measure and see where you stand. Repeat until satisfied. (this assumes you're crimping in a separate step from seating.)

February 3, 2008, 11:02 PM
ok new problem.

i just loaded 100 45acp's(230gr. JHP on top of 5.5gr of universal clays)

my kimber will shoot them just fine except i had one failure to eject(anyone know way this happened?) but in my dads P90 they will not feed, can anyone tell me way??.

February 3, 2008, 11:52 PM
What is the exact bullet you're using? Is this designed for 45acp or 45LC? What is the OAL? Can you tell us what is happening when it fails to feed? Is the HP catching on the chamber flange/opening? Does the first round chamber but subsequent rounds won't feed after the first is fired? Is the diameter of the loaded round, consistent up to the crimp area? Are the loaded rounds chambering part-way? or Not at all? Did you taper crimp or roll crimp? Are there any bulges in the loaded rounds that won't feed?

I'll ask you a question... Why does my head hurt?


February 4, 2008, 12:50 AM
there hornady 230gr. XTP JHP's in 45ACP. OAL is 1.208-1.214 on all of them(some factory rounds very more and some are longer and they work fine)

it wont eject the shot round and the next round wont feed, but they shoot fine in my kimber. it might be a head-space issue IDK.:banghead:

February 4, 2008, 08:06 AM
Factory XTP's are loaded at 1.235 O.A.L. That works well in my guns.

February 4, 2008, 12:06 PM
it wont eject the shot round and the next round wont feed, but they shoot fine in my kimber. it might be a head-space issue IDK.

Failure to EJECT, is not failure to FEED.

Failure to EJECT, is not failure to EXTRACT.

You must know these differences before anyone can give advice about why these loads do not function in the Ruger.

Could headspace affect Extraction/Ejection? Normally I would be doubtful, but if the cartridge wasn't seating properly in the chamber, then I could believe the possibility that the extractor was not engaging the brass correctly. I could see this, if the loaded/fired cartridge was allowed to go too deep into the chamber. Tighter tolerances in the Kimber may not be allowing this to happen. Too much roll crimp?

Anyone else care to chime in?


February 4, 2008, 12:38 PM
First thing to do is take the barrel out and chamber-check all of them.

If they drop in the chamber freely until flush with the back edge of the barrel, and fall back out freely, your crimp is fine.
As is your headspace.

Most likely an OAL issue.
Some guns won't work with some bullet shapes until you find the "sweet spot" OAL they have to have to feed.

Headspace will not prevent a round from ejecting.
If it goes in the chamber and fires, it should eject, no matter what the headspace.

It is also possible that your light loads using Universal Clays do not have enough power to fully cycle the Ruger.
Univ. Clays is not an especially good choice of powder for .45 ACP unless run at close to max pressure loads.

February 4, 2008, 06:56 PM

yes we took the barrel out and are reloads fit like factory loads, some were a bit "sticky" but we fixed that (sizer die wasn't low enough).

OAL is not the problem, Federal factory hydra shocks measure out to be about 1.206-1.207, CCI gold-dots are 1.214, and UMC ball are 1.224 and they all fire fine in the P90. hodgdon says 5.6gr. is max load(is this true?) and I'm averaging 5.5-5.6gr

is it safe to go up too 5.7-5.8?.

February 4, 2008, 06:57 PM

it had both FTF and FTE

the first round fired but didn't eject, then when we took the case out it would not feed the next round.

February 4, 2008, 09:23 PM
seriously i want to reload some more rounds, does anybody know whats wrong with my reloads or my dads P90??.

February 4, 2008, 10:10 PM
it had both FTF and FTE (eject)

Well then, I'm no expert like RC, but it would appear that there two problems. I would focus on one at a time.

Failure to Eject-

Is the slide cycling completely when firing? Will these reloads function fine when shooting single shot? (with/without a magazine inserted?)


February 4, 2008, 11:03 PM
i would say, try another powder, and see if that changes anything. do you know the spring pressure differeances (of the recoil springs) between the two firearms?? this might be the differance?

February 4, 2008, 11:45 PM
Taper "crimp" relies on neck tension for bullet retention, and to me is nothing but a bell removal die. Roll crimp actually bites into the bullet adding resistance to bullet movement along with neck tension, and definitely what I would want if shooting a revolver.

A bullet without a crimp groove was not designed to have a crimp "bite in to it".
The taper crimp is DESIGNED for semi auto pistol cartridges that are supposed to headspace on the case mouth l(even if the extractor prevents it from doing so).

The purpose is to restore the case walls so they're straight. Check out the dimensions of a factory round, virtually all of which are taper crimped, and then use your taper crimp die to duplicate.

Walkalongs' post accurately describes the proper use of the taper crimp.

Without a crimping groove (cannelure), the roll crimp does little more than deform the bullet.

The roll crimp works well for cannelured revolver bullets, or slight crimp over a wadcutter.

Semi-auto rounds still work, in spite of it, because the extracter prevents the improper roll crimp from allowing the case to travel too far forward, which could otherwise be quite problematic if the bullet didn't engage the rifling soon enough to still allow the firing pin to hit the primer.

February 4, 2008, 11:56 PM
yep my dies taper crimp(or it looks like it anyway).


my recoil spring in my kimber is heavier then the one in my dads ruger.

maybe next round i'll try a new powder but so far i really like the one i'm using.

February 5, 2008, 07:13 AM
Have you mic'd the outside of the case after crimping? The other thing that would affect feeding is the bullet profile. It could be just that your Ruger doesn't like the profile on the bullet you're using. I've got 2 Springfield XD's that don't like LSWC's no matter what I try.


February 5, 2008, 09:48 PM
that might be it, i'm gonna get some FMJ's and try it again.

February 6, 2008, 04:29 AM
On your FTF when you cycle the slide what is the bullet doing does it nose dive does it not try to strip it out of the magazine at all?

Talking about tighter tolarence I had a Kimber Ultra CDP and a friend with a Ruger P90 could Feed the lead that my Kimber did. I had to run a FCD ove it to get them to chamber in his gun. I'm not suggesting this I have other thought on your problems

First you say that the kimber has a heavier recoil spring and that you are running at or near max. Cut the powder back and try that you may be out running the gun. You have a max load on a light or worn recoil spring and the slide cycle faster than the magazine spring can push the next bullet up. If this works and the P90 has been around for a while I would then suggest that you buy your dad a spring kit there not really expensive but will make a world of difference and will also save the firearm from excesive abuse from worn springs.

February 6, 2008, 05:56 PM
It looks like they are getting caught on the feed ramp, i'll fire some off later and check again.

And you might be right a new spring might help a bit.

February 6, 2008, 09:59 PM
I load my 45s with roll crimp fairly heavy.bullet out 1/32.SWCL.3.6 gr /700X
all have factory springs.the theory on the bullet is it engages the rifling and jams to make the head loads follow one of the top shooters DINNAN of conn.50 ft stays in X ring 50 yds in 10 ring.I am not a top shooter by any means. :D

February 6, 2008, 10:13 PM
If there nose diving into the feed ramp that could be a magazine problem also, but I would try a lighter load and also get the spring kit. If your father left the magazines loaded all the time over the years this will reduce the power of the spring.

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