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bedbugbilly
03-20-2017, 11:24 PM
I may be "behind" on things but I ran across what was listed as "Lee's new collet crimp die" for 45 Colt on flea bay. I have never seen one before so I'm guessing they are fairly new. A quick check of Titan's site and sure enough, they show about five different calibers - 357, 44 mag, 45 Colt, etc.

I use their collet crimp on my 8mm and 30-30 and they work well . . . but straight wall pistol cartridges?

I am thinking about my 45 Colt loads - I strictly use the old style traditional FNRP in 200 and 255 grain - put a roll crimp on they easily. On several other designs, I've just used a taper crimp and have never had an issue in regards to boolit jump in my Uberti Cattleman.

I have thought about getting some powder coated 230 grain just to try for fun - in the traditional "ball ammo" style boolit for the 45 ACP - they wouldn't have a crimp groove but I figured a tight taper crimp on them wold be more than adequate.

The write up I read on the flea bay listing touted how easy it was to use on the "difficult to load" 45 Colt. Huh? i find the 45 Colt to be oe one of the easiest cartridges I've ever loaded.

So . . . why the marketing of a collet crimp for these pistol cartridges? Just something "new" for people to try or do they have a real advantage over a roll crimp or taper crimp die? I realize that a lot of these cartridges are now being used in lever guns, etc. - is it primarily for them or just "hype" and a new product to make sales? It's sort of advertised as making a secure crimp as on rifle cartridges and no crimp groove is necessary as it will creat it's own?

Most of what I've read as far as, say the 38/357, 44, 45 Colt, etc and lever guns is that a decent roll crimp is all that's needed. Is there something I'm missing? I'm certainly open to new things and would not be against trying one if I thought there was an advantage for it but off hand, I'm not seeing the need when you already have a good roll crimp or taper crimp . . . . unless there is an advantage to a rifle type crimp in a Ruger Only type load?

Thanks.

Jim

jmort
03-20-2017, 11:27 PM
They have been making them for years

http://leeprecision.com/45-colt-custom-carbide-factory-crimp-die.html

They work well for cast bullets

bedbugbilly
03-20-2017, 11:57 PM
Call me Rumplestiltskin and wake me up! I don't know where I've been as I never ran across them before for pistol. Or just never noticed them? I'm "old" so I'll use that as my excuse! LOL

Thanks jmort . . . . . appreciate the "wake up nudge"! :-)

runfiverun
03-21-2017, 12:23 AM
pffft.
the 45 colt and the others have got along just fine this long without any fancy crimp die, or second carbide ring to squish everything down to size.
I won't be looking for either one any time soon.

bedbugbilly
03-21-2017, 12:52 AM
runfiverun - I agree with you. Evidently these have been around for a while but I never noticed nor ran across one. If I'm understanding the write up correctly - this is not a die like the FCD with the carbide ring. It is like the collet crimp dies they make for bottleneck cartridges. I obviously have not known about this so my main question about them is "why".

For 38/357, 44, 45 Colt - let's face it. Regardless of who manufactures the die set, they come with a seating/crimp die. It's up to the reloader if they want to seat and crimp in two operations (I do). I've used roll crimp most of the time - on 38 Collt short/long I use a 9mm taper crimp die to crimp. On my 45 Colt, whenI first started reloading, I had a hodge podge of dies and used a 45 ACP taper crimp die for a long time before getting a proper seating/roll crimp die. Let;s face it . . . with a straight wall pistol cartridge you get many reloads out of casing whether you use a roll or a taper crimp.

Even on my 30-30 with lead, I use a roll crimp the majority of the time but i do have a collet crimp die if I want to use it.

So . . . I guess my curiosity is just peaked as to the "why' you would feel the need to have/use a die such as their collet crimp on a straight walled pistol casing? Not arguing if it is "right or wrong" - if someone uses them and likes them, maybe they can explain the "why"? Different strokes for different folks and that's fine - and there have always been "new and improved" methods, dies, etc. But if you buy a set of dies to reload 38/357/44/45 Colt and the normal set comes with a seating/crimp die, why would you spend more money to add one of these "collet crimp" dies for pistol load?

Or . . . is it a "competition shooter", super accurate/consistent crimp kind of thing that I'm just not considering since I don't shoot competition?

Nueces
03-21-2017, 10:55 AM
The older steel 45 Colt dies (mine were RCBS) were made for bullets larger than 0.452". Older cartridge drawings showed SAAMI loaded bullet diameter as 0.456" and early bores were 0.454". Those old Remington swaged slugs measured 0.456".

Modern 45 Colt bores go 0.452". When loading smaller 0.452" bullets with these old dies, the bullets were a fairly loose fit in the neck and the crimp die typically folded in only a part of the neck - had to step the case around to get a full crimp. I believe this sort of thing is what caused the poor rep of the 45 Colt in loading circles.

My revolvers call for a range of bullet diameters in this caliber, so I have accumulated a collection of sizers and crimpers - RCBS, Lyman, Redding, Dillon, Lee. A modern sizing die usually oversizes the case for a fat bullet. I solved my problem with larger bullets by trying a Lee factory crimp die as a case sizer. This is the die that has a carbide ring in the base, to insure that rounds are small enough to chamber. The story I heard is that Lee used carbide rings made too large for the case sizers in these crimp dies. So, the rings are larger than normal sizers and might work with larger bullets.

This did work. To make good choices among the sizers, I used some new cases and sized them with all my sizers, keeping notes on the resulting case mouth ODs. Did the same thing with neck expanders. Now, I choose what sizer to use based on bullet diameter and case neck thickness. I also have a small collection of new and old crimp dies, and know which ones to use with which bullet and case neck diameters.

The Lee collet crimpers will work with all bullet diameters, so it's much simpler and cheaper to keep one of these rather than a bunch of old and new standard crimpers. I will say that, with 0.452" bullets and Starline cases, my Dillon Case sizer and AccuCrimp dies produce the very best result. Rounds look to be right from Winchester.

ikarus1
03-21-2017, 10:58 AM
is this the same as the Factory Crimp Die? I use them since they resize down to the base, even if I don't tighten the crimp. They work well for that reason alone.

jmort
03-21-2017, 11:11 AM
No, it is not the same as the handgun caliber Factory Crimp Dies.

Nueces
03-21-2017, 11:37 AM
Lee's imprecise terminology has give us much misunderstanding concerning "factory crimp dies." There are two general types of FCDs, the collet, or rifle type, and the carbide, or pistol type.

The carbide pistol FCDs combine a standard roll crimp function with a carbide ring on the die base that is supposed to take out any bulges in cartridge diameter that might interfere with chambering. Those carbide rings are larger than case sizer rings, which makes them useful in sizing cases to accept larger diameter bullets.

The collet, or rifle type FCDs make use of a collet which closes about the neck to produce a crimp. The amount of crimp is adjusted by moving the die up and down in the press. So, they can be adjusted to use with fat or slim bullets and case necks. They are also useful in crimping the old WCF rounds, such as the 32-20 and 25-20, with their thin case necks. A standard crimper must be used gingerly on these rounds, to avoid damaging the case neck. The Lee collet crimper closes the crimp by side pressure, much reducing the danger of a collapsed neck.

Now, and for some time, Lee makes collet crimpers for handgun rounds. At first, these were made only for bottle neck cases, such as the 44-40. Now, they are available for straight cases, though only for the longer versions of such ensembles as the 44 Russian/Special/Magnum. Per the lee site, minimum case length is 1.285".

Because the term Lee Factory Crimp Die can mean two very different types of die, we get messy conversations in which folks are speaking of these different dies as one species. The term Lee Handgun Factory Crimp Die can now properly refer to the carbide ring version or the collet version. I propose we be specific when talking about these dies, using, for example, terms such as Lee Collet Crimper and Lee Carbide Crimper.

bedbugbilly
03-21-2017, 11:43 AM
Ikarus1 - no, it s not the same as the Factory Crimp Die that has the carbide ring in it. I have those for most of my pistol cartridges and use them at times depending on what I'm loading.

The die I am referring to is a "collet crimp die" - the same type of die that Lee produces for crimping bottleneck rifle cartridges. I use them for 30-30 and 8mm and do really like them. The one I'm talking about is for pistol cartridges such as 357, 44 and 45 Colt. When the casing and seated boolit is raised in to the die, a sectioned collet closes in around the neck of the casing and puts an inward pressure on it causing a crimp. Ifi it is like their rifle die, adjusting the die up and down in the press determines just how hard of a "squeeze" the sectioned collet puts on the neck to make the crimp.

Nueces - thank you for the information! I hadn't considered the discrepancies in the sizes which I know are and can be an issue with 45 Colt especially considering the variances in new and old firearms.

I only have one 45 Colt - a Uberti Cattleman and I consider myself very lucky as I have had no issues in regards to boolit sizes and bore size. My favorite slug is the Ideal/Lyman 255 gr. FNRP - (454-190?). The drop right at .454 and I load them "as dropped" and they shoot very well. I ran across several batches of commercial made lead boolits that are 200 gr FNRP that were sized .452 and with lubed grooves (I alox/paste wax the ones I cast) and they also worked very well out of my Cattleman. My cylinder throats work equally well with either .452 or .454 and I don't get any leading - am very happy with the revolver.

My cylinder chambers seem to be very generous and since I only have the one 45, using Starline Brass as well as some "range brass", I initially full sized them and after the first shooting, went to neck sizing them. Your comments did get me to thinking about "how" I load my 45 Colt though. It is the only cartridge I have where I didn't buy a complete set of dies (by the same mfg). I deprive all of my brass with a universal de-priming die. I remove all the de-priming pins from my FL dies (pistol dies). My FL die is an old Lyman A-A carbide. My expander die is an old Lyman A-A die with a expander stem like their "M-die". My seating dies are either an old RCBS or an old CH. My crimp is either an old RCBS, a old Herters (I think) 45ACP taper crimp or I use my Lyman steel tongs and 310 die to put a roll crimp on. A real "hodge podge" of dies but I load in batches and it works - loading the 45 Colt for me is very relaxing.

BUT - what you talk about all makes sense as it seems my biggest issue HAS been with the crimp and crimp dies that I have when using various boolits and the variation in diameter. My expander die, which is like an M-die makes the "getting of the boolit in" an easy task but then I do have to vary the crimp dies I use.

SO . . . "an old dog can learn new tricks" as they say. We are heading back to MI next week and when I get back, I think I just might order one of these collet dies to try out as it just might solve the issues that come up once in a while.

Thanks for your explanation - greatly appreciated!

Jim

ikarus1
03-21-2017, 12:49 PM
This is straight from the Lee website:
A carbide sizer inside the Carbide Factory Crimp die post-sizes the cartridge while it is crimped so every round will positively chamber freely with factory like dependability. The adjusting screw quickly and easily sets the desired amount of crimp. It is impossible to buckle the case as with a conventional bullet seating die. Trim length is not critical so this extra operation takes less time than it would if cases were trimmed and chamfered.Revolver dies roll crimp with no limit as to the amount. A perfect taper crimp is applied to auto-loader rounds. The crimper cannot be misadjusted to make a case mouth too small to properly head-space. A firm crimp is essential for dependable and accurate ammunition. It eliminates the problems of poor ignition of slow burning magnum powders


So depending on whether it's a revolver or autoloading cartridge determines what type of crimp on the FCD.

Then I see where they offer a collett crimp type FCD for the bottleneck PISTOL cases like FN 5.7, .357 SIG etc http://leeprecision.com/reloading-dies/hand-gun-dies/lee-bottle-neck-pistol-factory-crimp-die/

But I see no collett type crimp die for straight wall pistol cases like the OP has mentioned. What's the LEE part number on the side of the die?

jmort
03-21-2017, 12:53 PM
http://leeprecision.com/lee-collet-style-crimp-die/

ikarus1
03-21-2017, 01:00 PM
Yeah I neglected to look at the link in post #2. Their video says it's for cast oversize boolits. Dunno, I fail to see the need of that one over a heavy roll crimp in a separate stage.

jmort
03-21-2017, 01:14 PM
Then don't get one. I like the Redding Profile Crimp Die, but there are times when the collet die makes sense. For example, I have some bullets that are right near the end of cylinder. Any jump will render the revolver inoperable. You can use bullets that have a crimp groove in the "wrong" place, or no crimp groove at all where you desire a strong crimp.

r1kk1
03-21-2017, 01:40 PM
That's why I like taper crimp dies for hard kickers. No bullet jump. Works very well in my revolver.

Take care

r1kk1

DougGuy
03-21-2017, 02:17 PM
The collet crimp dies work very well for heavy boolits and slow powder like H110. It provides enough resistance against boolit jump from primer ignition, which taper crimp CANNOT do, and it allows a few extra nanoseconds for powder to light off before boolit movement occurs. It will lessen the spread noticeably over a chrony so it does do some things that other crimps will not do and you can document this with data obtained from your chrony, and your targets from a range session.

Also, these collet crimp dies are NOT for oversize boolits! The reality of it is that the collet will scrape the sides of the boolit IF IT IS oversized! The 45 die will handle a .452" but you will have to do more work on it to use it for a .454" boolit. Same with the 44 magnum, it's max is .432" and it may shave a tiny bit of lead even at that diameter.

The collet crimp die for straight walled pistol cases needs to be machined before you put it to work, the crimp band is too wide and sits too high on the case so that in it's as-issued state, it will crimp the sides of the boolit in front of the case mouth this is undesirable and I have modded a few of them to my liking. Here is a thread with pics detailing those mods:

http://castboolits.gunloads.com/showthread.php?201449-Question-about-type-of-crimp-required&p=2239315&viewfull=1#post2239315

Here are some Lee C452-300-RF collet crimped in Starline 45 Colt cases:

http://i1202.photobucket.com/albums/bb374/DougGuy/Reloading/0d3c189d-b085-4d95-a658-1f0f88b78255_zps3f37d14d.jpg (http://s1202.photobucket.com/user/DougGuy/media/Reloading/0d3c189d-b085-4d95-a658-1f0f88b78255_zps3f37d14d.jpg.html)

Lee C430-310-RF collet crimped into Starline 44 Magnum cases, modded collet crimp die did the cases on the left, standard roll crimp was used on the cases on the right:

http://i1202.photobucket.com/albums/bb374/DougGuy/Reloading/DSC01964_zps17b81bf2.jpg (http://s1202.photobucket.com/user/DougGuy/media/Reloading/DSC01964_zps17b81bf2.jpg.html)

Fired cases show complete opening of the collet crimp:

http://i1202.photobucket.com/albums/bb374/DougGuy/Reloading/DSC03150_zps2fffcc0c.jpg (http://s1202.photobucket.com/user/DougGuy/media/Reloading/DSC03150_zps2fffcc0c.jpg.html)

jmort
03-21-2017, 02:31 PM
I was not going to comment, but there is no way a taper crimp crimp will come close to a collet crimp. Fully agree with the modification of the collet fingers.

r1kk1
03-21-2017, 03:07 PM
191334 191336 191337 191338

Yeah taper crimp works. I burn kegs of 110/296 and 4227. The 500 Linebaugh load I use for 350 grain bullets is 36 grains of H110/W296. Not a max load but will carry that to close to 1600 fps. A nice target load is using a 310 grain bullets over 32 grains of 4227. I took the Catalina Goat this year. My wife took a Corsican Ram with her necked down 475 Linebaugh to 45 caliber revolver also. That will probably lead to a discussion of why bottleneck cartridges don't work in revolvers but they do if designed right. I do have a Hornady roll crimp die for this cartridge also. I have the TC die adjusted to where the chronograph gave me good readings and the revolver functioned well. Recoil is quite brisk and requires gloves.

Dave at CH4D challenged me to the idea of using TC or taper crimp dies against roll crimp. I tried it first in a 44 mag and I have a Dan Wesson in that caliber. It worked. Extreme spreads are single digits. It will average 1570 fps using Blue Dot and a 255 gr wc from a custom Lee mould. That revolver and load can make anyone a great shot.

take care,

r1kk1

jmort
03-21-2017, 03:16 PM
Dave is a great guy. And no doubt the taper crimp works for you. But there is no sane reason to claim it either equals or exceeds the potential of the collet crimp. No reason to go there.

TNsailorman
03-21-2017, 03:37 PM
I have never felt the need for a factory crimp die or collet crimp die. I use the roll crimp die feature of seating dies on rifles and revolvers, and the taper crimp feature on seating dies on pistols. I have bought a profile crimp Redding die to use on the .41 magnum but that is only to keep from having to seat and then re-adjust the seating die. Call me lazy. I tried one factory crimp die for the 30-30 some time ago but either I didn't adjust it right or something but it was damaging the case mouth more than I wanted, so I sold it. I have no problem with people who extol the virtues of the Lee factory crimp die, I am just an old dinosaur and like to do things the way that I have become accustom to. I say use the die or dies that you are comfortable with and enjoy reloading for what it is, an enjoyable pastime. james

dragon813gt
03-21-2017, 04:24 PM
Pictures are worth a thousand words.

Carbide Factory Crimp Die
http://leeprecision.com/userfiles/images/38_FCD.jpg

Collet Style Crimp Die(no cutaway available)
Yes, I'm aware of how the instructions are labeled in the packaging.
http://leeprecision.com/images/P/90969-01.jpg

Short Bottle Neck Collet Style Factory Crimp Die
http://leeprecision.com/graphics/shoppingcart/bottleneckfcdie.jpg

Factory Crimp Die
http://leeprecision.com/userfiles/images/30-06_factorycrimp.jpg

If you notice the name is different for every one. Same word are used but they all have different names. You need to call them by the proper name so people know which one you're talking about.

r1kk1
03-21-2017, 06:03 PM
Dave is a great guy. And no doubt the taper crimp works for you. But there is no sane reason to claim it either equals or exceeds the potential of the collet crimp. No reason to go there.

JMort you made the statement about taper crimp die not working. I posted a revolver with about twice the recoil and picture where I made meat with it. I've proved taper crimp die's work. You have not proven where the Lee Collet die is better. I have a plethora of crimp dies and quite a few LEE pistol and rifle. I use them for working up loads for different wildcat or obsolete stuff and then I order my favorite crimp die from one of four manufacturers. I like the Redding Profile Crimp Die and used that for years on magnums up to 454 Cassull. They sit on the shelf for the most part. I used Lee's Factory Carbide Crimp die in 10mm for a 400 GNR lever action. This is the 30-30 blown straight. It worked but it was replaced by one made by CH4D. I still have the die. I have a 357 wildcats, 44, 41, 45, 47, and 50. There are no Lee products I used for the 500 Linebaugh for a reason. That includes their Custom Services side. I have a Redding 375 Winchester Profile Crimp die, taper crimp die and a roll crimp die. I also have a 458 Win Mag that sports all three dies. Love CZ rifles and Savage!

So I guess the burden of proof is your's not mine. The Lee Collet die reminds me of the old stake crimp although the pattern is tighter.

take care and peace,

r1kk1

jmort
03-21-2017, 06:31 PM
"JMort you made the statement about taper crimp die not working"

No where in this thread.
Where?
When?
That is a lie

All I said was

http://castboolits.gunloads.com/images/buttons/viewpost-right.png (http://castboolits.gunloads.com/showthread.php?p=3993057#post3993057)
"Dave is a great guy. And no doubt the taper crimp works for you. "

r1kk1
03-21-2017, 06:40 PM
I was not going to comment, but there is no way a taper crimp crimp will come close to a collet crimp. Fully agree with the modification of the collet fingers.

What about this!

jmort
03-21-2017, 06:44 PM
That does not say a taper crimp will not work. It states that the collet die has far more crimping potential. The preceeding post from Doug clearly explains why and how. I will say it again, I have "no doubt the taper crimp works for you."

r1kk1
03-21-2017, 06:59 PM
I reread Doug's post. My post #18 shoots it down no pun intended.

Are you open to results for 44 Mag TC and 454 Cassull lever action with a TC die? I already have the dies. . .

r1kk1

jmort
03-21-2017, 07:06 PM
I have no doubt you have great results with the taper crimp. Dave is a great and knowledgeable guy. CH4D is a great operation. We will have to disagree. I will defer to you as a general matter, as you are one of the more knowledgeable members.

r1kk1
03-21-2017, 07:24 PM
I have no doubt you have great results with the taper crimp. Dave is a great and knowledgeable guy. CH4D is a great operation. We will have to disagree. I will defer to you as a general matter, as you are one of the more knowledgeable members.

Agree jmort. We agree to disagree. Fair enough.

r1kk1

DougGuy
03-21-2017, 07:37 PM
I reread Doug's post. My post #18 shoots it down no pun intended.
r1kk1


Nosir, your #18 post does not shoot down the comment I made about the taper crimp die not holding heavy for caliber boolits against primer flash, recoil, etc.. And I MAINTAIN that statement.

Now... You may be calling something a taper crimp when it CLEARLY is a rolled crimp with a compressed ring at the case mouth VERY similar to the collet crimp's work!

This (see red arrow) is NOT a taper crimp!

http://i1202.photobucket.com/albums/bb374/DougGuy/Reloading/500%20Linebaugh%20Cartridge_zpsj5mwlbz6.jpg (http://s1202.photobucket.com/user/DougGuy/media/Reloading/500%20Linebaugh%20Cartridge_zpsj5mwlbz6.jpg.html)

Taper crimp refers to the gentle taper used in autopistol ammo that must headspace on the case mouth, and I don't care HOW MUCH neck tension you have, you will NOT hold a heavy boolit in a big bore hand cannon with a taper crimp as applied to a 45 ACP case. No way on God's green earth will this happen. If it did, people would be using it constantly to extend case life.

THIS is a taper crimp!

http://i1202.photobucket.com/albums/bb374/DougGuy/Reloading/DSC03202_zps29ffd571.jpg (http://s1202.photobucket.com/user/DougGuy/media/Reloading/DSC03202_zps29ffd571.jpg.html)

Not sure what die you used for your version of a taper crimp, but I see no taper at all, I see a rolled crimp with a crimped ring exactly like my collet crimp does, just narrower.

DougGuy
03-21-2017, 07:43 PM
This is the modified collet crimp die's footprint on a 45 Colt case with a slightly harder C452-300-RF than the softer boolit I posted in my earlier reply. This crimp looks more like your "taper crimp" than a real taper crimp..

http://i1202.photobucket.com/albums/bb374/DougGuy/Reloading/b0365352-e008-4573-ae2e-859b8a99fe82_zps7c72c5cb.jpg (http://s1202.photobucket.com/user/DougGuy/media/Reloading/b0365352-e008-4573-ae2e-859b8a99fe82_zps7c72c5cb.jpg.html)

DougGuy
03-21-2017, 07:53 PM
One more comment about your crimp,,, Notice anything similar? Notice how your boolits don't jump crimp? Mine don't budge at all. I thing the imagery speaks for itself.. What we have here is two slightly different but very effective crimps.



http://i1202.photobucket.com/albums/bb374/DougGuy/Reloading/500%20Linebaugh45Colt640_zpsispnnrnv.jpg (http://s1202.photobucket.com/user/DougGuy/media/Reloading/500%20Linebaugh45Colt640_zpsispnnrnv.jpg.html)

I went back and looked at your die photo.. You may SAY this is a taper crimp die, and Hornady may have marked it as a TC die, but the application you use it for provides the SAME style crimp as my modded collet crimp, a tightened band that firmly presses into the side of the boolit. Nosir your #18 post is not proving me wrong, it's proving me RIGHT. You say ES is in single digits. SAME thing I said. Your crimp and mine are doing the SAME thing.

http://i1202.photobucket.com/albums/bb374/DougGuy/Reloading/Hornady%20Taper%20Crimp%20Die_zpsd1f0ejy9.jpg (http://s1202.photobucket.com/user/DougGuy/media/Reloading/Hornady%20Taper%20Crimp%20Die_zpsd1f0ejy9.jpg.html )



But.. This post was not and is not meant to spark argument. It is discussion, and the OT of the thread was about collet crimp die for straight walled pistol cartridges, and my point is that they are very beneficial and very useful, and could be a life saver if you carried a heavy boolit in a big bore revolver in dangerous game country. I would NOT want to carry ammo that had a snowball's chance in hades of jumping crimp. The collet crimp is an excellent way to hold on to a heavy boolit.

Also, the softer the alloy, the more crimp is needed because softer lead boolits will swage against the crimp and the base of the boolit can move forward. Hardcast needs 40% of the crimp the same boolit in 50/50+2% needs.

jetinteriorguy
03-25-2017, 05:36 PM
Since I mostly shoot Copper coated or HiTec coated bullets I love the Lee Collet crimp die since it doesn't cut through the coating like a heavy roll crimp can. I use them in both my .357 and .41 mag revolvers and especially my levers.

1hole
03-29-2017, 04:09 PM
IME, Lee's collet crimpers are the very best available; the major advantage of the collet crimper is it's not so case length sensitive. To obtain consistent crimps with a conventional taper or roll crimper demands the cases be very near the same length and I don't enjoy case trimming.

The major advantage of Lee's excellent post sizing "after seating" carbide ring for straight wall cartridges is to insure easy chambering of every round and it works as advertised. It IS possible for the die to reduce the diameter of handgun bullets after seating and that isn't helpful for best accuracy but sometimes absolute reliability in a handgun takes precedence over the absolutely tiniest groups.

Those shooting from fat chambers probably won't need the carbide FCD at all but the current fad of using fat cast bullets in cases of differing wall thicknesses can easily result in cartridges that won't reliably chamber in tight chambers and jams can result in disaster. I don't use Lee FCD crimpers on my .38 Spec. target ammo but I sure do on ALL of my .45 ACP. .357/.44 Mag ammo dedicated for "social work".
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