45 ACP crimp or not


March 24, 2011, 09:24 PM
I have reloaded rifle bottle necks and doing fine with that. Now am learning to reload pistol. My Hornady manuel quotes this...
(Little or no crimp should be used,as the 45 automatic headspace on the mouth of the case.) What are they talking about ? Is this a miss print. anyhow should I crimp or not ? I have a Colt model M1991A1 45 acp. My COL is 1.26 =barrel drop fit.The bullet is Speer lrn .452 , 230gr. What do you all think ? :)

If you enjoyed reading about "45 ACP crimp or not" here in TheHighRoad.org archive, you'll LOVE our community. Come join TheHighRoad.org today for the full version!
March 24, 2011, 09:30 PM
That's not a misprint. Do exactly that. Crimp a little to none. Just get to where the crimp ring kisses the case mouth at the very top of the stroke, and you'll be good. This will take any flare off the case mouth, and you might even shave a little brass off the edge, if the shoulder is particularly sharp. That's fine. It'll still space off the mouth.

Calipers on the edge of the mouth should show 4.68-4.72". If your cases measure within spec with no crimp and they chamber, then you don't need to crimp. Make sure they pass the chamber check by falling in/out easily. But I suggest you still set your crimp ring so that it barely touches, in case you get a longer than normal case. That one will get more flare, and the ring may iron it out.

If you leave a little bit of flare, the worst case is that you have a kB, because the round doesn't chamber all the way.

March 24, 2011, 09:32 PM
Im not a veteran reloader, but what I do is set my crimp die to just remove the flare from the powder die. This is what I also learned from the man that has been helping me reload. I've reloaded 4k 45's this way, and they shoot very accurate out of my PT1911. Good luck to you.

March 24, 2011, 09:45 PM
Thanks for the help,I will lightly crimp. My case mouth measures .470 so I guess that should be good.
Also does a flat WC shoot more accurate than a RN ?

Red Cent
March 24, 2011, 09:50 PM
Simplify the matter. Solve the crimp question. I put the Lee Factory Crimp die in the last station of the Dillon. This die simply squeezes everything to factory specs. I get those sideway looks when I say use the FCD. Some have told me "learn to reload" :). Nawww. Too lazy. The FCD makes you look like an expert. Just don't spread it around. Put a smudge of graphite on your brow and exclaim "Whew!. Just spent all after noon making sure these loaded rounds are RIGHT."
i used to drop every 45 round in to a chamber gauge. The rejects, I did them again. No more. They chamber beautifully.


Seriously, you should taper crimp a semi auto round and roll crimp revolver rounds. Taper crimp simply flattens the case to the bullet leaving a fine edge that you can detect with your fingernail. If that is not there the case will go too far into the barrel and not fire. Look in the chamber end of a 45 acp barrel. That little ring is where the mouth of the case seats and stops.
Roll crimp is that. The die rolls the edge of the case into the bullet for super retention.

March 24, 2011, 09:52 PM
The round looks good. .470 is fine. Yes, in general a WC or SWC will shoot a little better than a RN. One big advantage in target shooting is they cut a bigger hole and might get than next scoring ring the RN misses.

March 24, 2011, 10:14 PM
OK, thank you for helping me.

March 27, 2011, 10:30 PM
In most manuals, there is a schematic drawing of the cartridge with a nominal diameter value for case mouth of a loaded rounded. Adjust your crimp to produce that diameter and you should be fine.

March 27, 2011, 11:27 PM
Yes, crimp. With .452" bullets, your crimp should measure in the neighborhood of .472". With .451" bullets, about .001" less.

March 28, 2011, 05:43 PM
I shoot competitive Bullseye, so my suggestions come from that perspective. I shoot nothing but SWC 185 and 200 grain cast or swaged bullets.

I have loaded & shot over 50,000 45ACP rounds in the last 12 years and tested thousands of rounds in a Ransom Rest.

The amount of crimp is dependent on your chamber dimensions, powder choice, bullet choice, and brass choice.

If you're loading them for casual shooting, crimp to whatever you want. You mention a COL of 1.26" measured per a barrel drop. Make sure your OAL is at least .001 shorter than the hood length. If you get into a lengthy match or practice session the fouling buildup both in the forcing cone and slide face can result in jams in feeding. Don't ask how I know.

If you're loading for competition, 100% feeding is a must. I taper crimp my short line (50' and 25 yards) loads from .465-.470 (100% reliability is a must). If I'm loading swaged lead bullets (very soft) a light crimp is required to avoid deforming the bullet (.470). If I'm loading my cast bullets (harder) I crimp to .467-.468. Never over .468 because I'm looking for the reliability factor and I can't afford to have a round fail to chamber because of fouling at the end of a match.

My long line loads (50 yards) are crimped .468-.470 with all brass except Remington. Remington is thinner and requires .466-.467 to achieve the same level of bullet pull from the case and the same level of accuracy. My first Kart barrel in my wad gun wouldn't shoot unless I crimped them to .463, it was a tight chamber and didn't like anything over .465.

Some powders also will be very dirty if there isn't enough resistance when the round is fired. Experimentation will tell you.

Keep records of what you've shot and the results. Try the same amount of crimp after 300 or so rounds and see if there is any issues. If there isn't you're good to go. If there is, give it a bit more crimp and retest.


March 28, 2011, 08:38 PM
Sometimes with wadcutters a little crimp can help feeding, but too much can hurt head spacing as you read.
My Sig likes a taper crimp of around .467" with semi wadcutters seated deep.

I find the SWC's are the most accurate for .45's, some of which may be due to being seated so squarely by pushing on the shoulder.

March 29, 2011, 02:11 AM
I found Radcom's thread on a search so I apologize if this appears to be a hijack. My question though is how do you tell if you are taper crimping too much?

I am reloading Horndy 230FMJ RN in Rem cases. The dies are RCBS carbide and if you havn't guessed by now I am very new to reloading. I will be shooting these out of a SA XD 45 5" barrel using Hodgdon Clays and Fed 150 primers, if any of this matters.

Right now my gut is telling me I am taper crimping too much. What happens if I taper crimp too much? From what I have read so far I just need to crimp enough to knock the bell off the casing left from the expander die.

March 29, 2011, 02:46 AM
You can tell by how the case mouth digs into the bullet. Hold up the bullet against a light source. Look at the curvature of the case mouth. You wanna see a barely visile curve into the bullet in the last .010 of case length. The case mouth should measure about .472" at that point.

March 29, 2011, 07:36 AM
I use a loupe, as well as good light, to check my crimps.

March 29, 2011, 10:11 AM
Excessive crimp will result in too much bullet/neck tension and spike the pressures. If you're working with a mild target load, you may get away with it.

DON'T COUNT ON IT!!! You should taper crimp enough for reliable feeding in a dirty chamber, no more.

When I went down to .463 it was by a thousanth of an inch with a target load. I watched my primers and cases like a hawk for pressure signs. I know of one guy who went below .460 and liked to load them hot. He has ruined 2 custom guns and upset an excellent gunsmith.

For normal casual shooting .468 would be the minimum I would ever give a blanket recommendation for. Unless the person is a very experienced handloader and is a precision shooter needing 2" or less groups at 50 yards. I would require more information available about the barrel, gun, and ammunition purpose for any other suggested crimp.


March 29, 2011, 11:14 PM
Thanks for the info guys. I can visually see a rounding and without double checking all I do not remember going below .468 with most .4695 or above.

my gun is an xd45w/ a 5" barrel. Gun is all stock. My loads are the basic starting load of 3.7grns of Clays in Remington cases, Federal 150 primers, and Hornady 230 fmj rn bullets. Case over all length is 1.99" to 1.20" Nothing exotic and this are just for casual shooting.

March 30, 2011, 12:06 PM
Excessive crimp will result in too much bullet/neck tension and spike the pressures

It will not. A taper crimp does nothing for case tension on the bullet, nothing.

March 30, 2011, 03:10 PM
Update, this is my final product.. went to the pistol range and shot 21 rounds with no problem.I believe I have a light taper crimp and I had to seat the bullet first then taper crimp.Also using 5.4 gn. Unique powder.
Barrel Drop test every 5th loaded round.What do you think of my crimp from the pictures ? :)

March 30, 2011, 06:45 PM
That is a lot of taper crimp.

Here is one of mine.


March 30, 2011, 07:08 PM
I picked out another round from a lot of 250 of the Berrys 230 Gr RN I loaded some time back. I picked one that showed as much crimp as any of them, meaning it is one of the longest cases. It is .471 at the case mouth, and .472 below the crimp mark. I adjust my crimp die so all the shortest cases get the bell completely removed and the longest cases get .001 to .002 crimp max. You can see where the crimp die contacted the brass. They were loaded to 1.265 (+/- .002)


March 30, 2011, 07:45 PM
OK, from the looks of your ammo I do have two much taper crimp.I reloaded 140 .
I got to shoot them up and hope everything goes well.
The next time I reload I will try to get those dimensions.:)

If you enjoyed reading about "45 ACP crimp or not" here in TheHighRoad.org archive, you'll LOVE our community. Come join TheHighRoad.org today for the full version!