How much crimp? Lee FCD guidance sought.

[CoastiesDad]

I am new to reloading. I have read crimp descriptions in may forums and books all without pictures. It is a very hard subject to understand, until this thread started. I have read it from the 1st post and followed all the replies (many times). The photos included with the posts make following the written description very understandable and is what is missing in other forums and books. I want to thank everyone who contributed to it. I now have a very good understanding of the subject.

[Walkalong]

A pic is worth a thousand words they say.

I am glad the thread was helpful. Welcome to THR.

[Winston_Smith]

Hi Walkalong,

Do you have pictures of correct crimps for rifles (.223/,308)?

[Walkalong]

Taper Crimp on .223 - Using a Redding Taper Crimp Die in a separate step.



I do not crimp accuracy .223 loads, just blasting/plinking/SHTF gotta work ammo. A roll crimp will work as well, but is much less tolerant of inconsistent cannelure placement and brass length. I still trim all my .223 brass, even when taper crimping.

I don't crimp .308. I don't load any plinking/blasting .308. If I did, I would, but I only load it for accuracy.

Neck tension is all you need for most applications with either caliber.

[Winston_Smith]

Thanks Walkalong, I am going to play around with my Lee FCD now that I know what I am shooting for. I will try to take some pics along the way.

Great thread BTW.

[Walkalong]

Took me many pics, as usual, but here are a couple.

7.62 X 39 - Hornady 123 Gr FMJ - Lee FCD die crimp




Looking forward to your pics.

[Winston_Smith]

Ok, here we go. My first attempts with the Lee FCD on .223 (with practice brass).

1/4 turn passed touching the shell holder


1/2 turn


3/4 turn


1 full turn

[Winston_Smith]

How does this one look Walkalong?

[Walkalong]

It did not catch much of the case.

It looks like you need to take a little off the bottom of the collet to move the crimp down some, or you trimmed your brass too short. You would, of course, have to re-adjust the die down a bit afterward if you removed some material from the collet. A different shell holder might work better.Yours may be a little high.

The easiest way would be to trim your brass to match your collet, as long as that ended up with a reasonable brass trim length.

If it doesn't work at a reasonable trim length, assuming an in spec shell holder or plate, then the thing to do is trim the brass to the suggested 1.750 and cut the bottom of the collet down to fit the brass length. Easy to do with a lathe, but can be done VERY carefully with a file and sandpaper. The thing to watch for is to keep it square.

The case mouth must align properly (up and down) with the crimping part of the die. That relationship should remain constant, no matter how far you turn the die down. Turning the die down further will crimp deeper, but it should crimp in the same spot on the neck since the brass is riding up and down with the collet, not the die.

Turning the die down too far will get a crimp like your "1 full turn" pic. Kind of smeared looking.

I believe you ended up turning it down too far, trying to get more crimp, because of the poor relationship with the case mouth. IMHO - AC

[Winston_Smith]

Thanks for the info Walkalong. These were trimmed to 1.750" and crimped on a Co-ax so there isn't much I can do about the shell holder (unless I buy the adapter).

These were 1/4 turn after touching the shell holder, does the crimp depth at least look OK?

I will trim a few at 1.760 and see how it works.

I was under the impression that the FCD was not very sensitive to trim length.

[Walkalong]

It is much less dependent on trim length because it is not rolling or bending over the case mouth, just pressing it inwards at 90 degrees.

The collet still has to be in spec.

Crimp depth is hard to see, but looks light.

[baddoggie]

This is my first post or reply in this forum but after seeing the excellent pictures and reading the info posted I had to say something! I have been reloading only a year or so but have read extensively on the subject but have never seen any book show examples of crimping as I have seen here. Great work Walkalong and all who posted to this subject. Many thanks and I'll be spending much more time here!

[Walkalong]

Light Taper Crimp on some .45 ACP Loads

[Walkalong]

I don't know who made these. Haven't loaded any in a while. The box says Cullman Al., and that's all. The case mouth is right where the full diameter stopped. I could have roll crimped over it, but I chose to seat them to there and apply a very light taper crimp. They shot quite well, not surprisingly, at an Avg 742 FPS. I will probably try a bit more taper crimp next batch. Still light though.

Very Light Taper Crimp on .38 SPl HBWC

[Walkalong]

This time I seated the HBWC to 1.175 instead of 1.195 O.A.L. and used a light Roll Crimp over that little ledge where you can see some lube.

Light Roll Crimp on .38 SPl HBWC

[Walkalong]

This time I seated the HBWC out to 1.335 O.A.L. and used a light Roll Crimp in to the cannelure, like it is intended to be used.

Light Roll Crimp in to the cannelure on a .38 SPl HBWC

[ljnowell]

I generally put the same crimp on my 45 colt target and full power loads. Both pictured are Missouri Bullet products, 255swc and a 300gr ltc. The 300gr has wo crimp grooves, so I seat the bullet out longer at the second groove. I consider both to be heavy crimps.

[GMFWoodchuck]

My only question is that a crimp is typically used to keep the bullets in place during the recoil of the firearm. That to me says a 500 S&W mag would need more crimp than a 38 special. Why would a person use the "same" crimp on everything if a light crimp is equally effective? Wouldn't a light crimp be easier on the brass if it suffices?

As far as the "non" typical use it's used to make more consistent ignitition leading to better accuarcy with "magnum" and therefore "harder to ignite" powders. Has anyone been able to determine this to be true to any appreciable degree? I ask only because I've tried crimping for my rifle (I don't have a handgun) and I couldn't see a difference, except that it was a waste of brass on the first few as I squished some of them and a waste of time.

[ljnowell]

My only question is that a crimp is typically used to keep the bullets in place during the recoil of the firearm. That to me says a 500 S&W mag would need more crimp than a 38 special. Why would a person use the "same" crimp on everything if a light crimp is equally effective? Wouldn't a light crimp be easier on the brass if it suffices?

As far as the "non" typical use it's used to make more consistent ignitition leading to better accuarcy with "magnum" and therefore "harder to ignite" powders. Has anyone been able to determine this to be true to any appreciable degree? I ask only because I've tried crimping for my rifle (I don't have a handgun) and I couldn't see a difference, except that it was a waste of brass on the first few as I squished some of them and a waste of time.

It really depends. I have sen airweight 38s that would pull bullets better than my kinetic hammer, and 44s that wouldnt budge with a taper crimp. I like a moderately heavy roll for consistent ignition on my revolver cartridges.

[Seismic Sam]

Going all the way back to the beginning of this thread, what I noticed was that a .005" flare is WAAAYYY too much to begin with, so the resulting crimps are skewed by how much the case mouth is expanded by to start with. You only want to expand the case mouth enough so that the first 10 mils or so of the bullet base barely fit into the case. With cast lead bullets, it's pretty easy to see because if the flare is not enough, you will start shaving lead. If you get the flare perfect (requires about 4 or 5 tries) the bullet base will just fit, and the case mouth diameter will increase by LESS than a mil after the bullet is run into the case. That's how you want to set your expander die.

The other issue is measuring, in mils, your crimp. None of this light, medium, and heavy qualatative stuff. To begin with, you take a round with the bullet seated according to the directions above where there is little to no case mouth expansion after bullet seating, and measure the case mouth diameter.

Then apply the crimp, and using the narrow inner edges of the caliper jaws, measure the diameter of the case mouth right at the very end. This is kind of a touchy-feely thing to get the caliper jaws level across the case mouth, but you can get the hang of it. Typically, you want a case mouth diameter reduction of .003", for stuff like 35& SIG and hot 10mm loads. For hot 44 mag and 50 AE loads, you want .005" reduction, and for the Smith 500 you want a solid 7 mil crimp to keep that bullet in place with hot loads. (Like a 325 grain JHP @ 1900 FPS )

[Walkalong]

Remington 110 Gr JHP in .357 brass with a bullet sitting on a .38 Spl case to show the cannelure well.

I used a Hornady seater to seat and crimp in the same step. (Same as Post #50)

Medium Roll Crimp on a Remington 110 Gr JHP

[Lee Roder]

Going all the way back to the beginning of this thread, what I noticed was that a .005" flare is WAAAYYY too much to begin with ...

I was just trying to make crimping less subjective. The Lee loader's flare tool, being just about idiot proof, provides a convenient target flare when using "real dies" and a press instead of a hammer. It's not an unreasonable amount.

To see why, consider the outside diameter of my sized cases generally run 0.373" - 0.374". My brass thickness (Winchester, Remington) typically measures about 0.010" and this tends toward "thin" in my experience, some brass is a bit thicker. A bullet diameter 0.358" (or larger!) has to fit into a mouth flared to at least this inside diameter to prevent shaving, requiring a minimum case flare of 0.358+0.010+0.010-0.374 or 0.004"

This is not significantly different from my quoted 5 mil figure given all the variability inherent as to bullet diameter, brass thickness and case size.

[Walkalong]

a .005" flare is WAAAYYY too much to begin with

I don't think .005 is waaay too much.

Lee Roders flair in the pics in post #1 is a bit more than needed, but I wouldn't call it excessive for lead by any means. Any more than needed does overwork brass of course, and (IMHO) too much can also make seating the bullet straight a bit tougher.

[Walkalong]

I just got these Berry's 148 Gr HBWC's. I have shot their 148 Gr DEWC before with good success, but not these. I loaded them at 1.402 O.A.L. (About .125 out of the case) Crimp is about .001 to .0015

Light Taper Crimp on a Berry's 148 Gr HBWC

[Walkalong]

Somehow or another I screwed up the pic/description in Post #53. Here are the correct pics and descriptions.

Roll Crimp on a Winchester 55 Gr FMJ in .223.


Taper Crimp on a Winchester 55 Gr FMJ in .223.


The Taper Crimp was done in a separate step with a Redding die. The roll crimp was done in the same step with a Redding seater die.