Lee Factory Crimp Die vs Collet Die

[RichO]

This is my first post here, but I've been reading for a few weeks.[smilie=w:

I have a Lee FCD I have been using for my 30-06 and was wondering if the collet die works the same way in reducing the neck for bullet tension. I don't have a collet and was considering a purchase but it looks the same as the FCD except for the depriming rod.

I have pulled some dimensions of the neck area of a full sized, fired, and FCD only listed below, anyone use the FCD for neck sizing? I sized the FCD to the point where the bullet tension was just able to hand remove the bullet without the crimp applied. I know I just should just spring for the collet die, but do they perform the same task? Or does the collet die size the neck further down the neck for better tension?

Full Sized Fired FCD
Case End 329.5 344 335
Mid Neck 331.5 341 340
Neck at Shoulder 333 345 340.5
Interior Case Mouth 301.5 310 307

Rich

[texassako]

They have 2 different purposes. FCD is for applying a crimp. The collet die is for neck sizing the brass. FCD only touches the case mouth, collet sizes the whole neck.

[MT Chambers]

The resizing die in your 2 die set is all that is required, toss the rest.......if you are not happy with case neck tension, get a diff. sized expander ball or M-die. The excellent Redding S-bushing dies have interchangeable bushings and would do the same thing but are costly.
Any good quality die set should provide proper case neck tension on such a common cartridge/size, you should not need anything else, for cast bullets you might be well served with a "M" type expander of your specs, which will expand and flare your case necks.

[RogerDat]

I have been doing a bunch of research on this subject in order to purchase dies for 303 British, ended up calling Lee for more information on their dies.

The collet die only sizes the neck of the case, which works the brass less than the full length sizing die. Avoids pushing the shoulder of bottle neck cartridge brass down, then firing pushing it forward, sizing pushing back down again. Eventually the shoulder gets weak. Generally collet die sized brass needs to only be shot in the gun that it came from since it is formed to that gun rather than full length sized back to original specifications.

For rifle the Factory Crimp die applies a crimp to roll the edge of the neck in to more firmly hold the bullet in place. Not always needed but if the ammo experiences rough handling or recoil jarring it keeps the bullet from moving. By adjusting the FCD you can control the amount of crimp but the FCD is not designed to size the neck to specification, it is in addition to sizing.

If the neck is properly sized and you just going to carry a box of your reloads to the range no need to crimp. Unless you are going to hunt with your own ammo and that you might want to crimp so having your target practice and hunting rounds be the same.

If you are loading cast you may as MT chambers said need some sort of neck flaring die to keep from shaving lead which distorts your bullet. Lee has a universal one for about $13 or other die brands have them. If you are loading jacketed bullets then the chamfering you would normally have done to the case mouth as part of prepping the brass should be sufficient "flare" to allow the jacketed bullet to enter the neck without shaving.

FCD or no FCD is a topic that folks seem to have a strong opinion on, some say not needed, some say they work great. The phrase a solution looking for a problem comes up from those that are not fans. One thing FCD does allow is crimping a bullet further forward or back of any crimp groove the bullet may have, or even when bullet has no crimp groove. Helps if you want to bring the bullet forward to the point where it engages or nearly engages the rifling of the barrel.

The FCD's other claim to fame is that unlike a crimp applied during seating it is not as sensitive to overall case length for how far it rolls in the edge of the case. This it is alleged that the more consistent crimp yields more consistent pressure when fired.

[DougGuy]

There is a collet style crimp die as well as a collet style neck sizing die. They both do different things. The collet crimp is great, -especially- if you seat out .020" or so short of engaging the rifling and the cannelure is already forward of the case mouth.

[RogerDat]

I think Lee is all but eliminating the tradition roll crimp feature in the seating die, calling theirs a Dead length seating die. In favor of the separate FCD which I think is a collet style. But frankly I go nuts trying to compare the dies from different companies. Every company puts lots of branding names and why theirs is best information out but straight info that would allow you to compare theirs to another companies? Eh not so much. How they can come up with so many ways and names for different dies for what always boils down to de-prime, size, seat, charge and crimp is beyond me.

I liked how DougGuy put it better than how I did on being able to crimp where it works best for your firearm.

[44Vaquero]

Lifted directly from Lee's web site:

The
Lee Collet Neck
Sizing Dies (http://leeprecision.com/reloading-dies/rifle-dies/lee-collet-dies): Use these dies for best accuracy, longest case life
and no resizing lubricant. Only the neck of the case is resized the body is
untouched so it retains the perfect fit to your guns chamber. Cases should have
been fired in your firearm only and reloaded rounds are intended for use in just
one firearm. These dies are the favorite of the bench rest crowd as there is no
other die that can produce a more accurate cartridge.

If
you intend to reload cases fired in others guns or you are reloading for more
than one gun select the Deluxe Rifle Die
Set (http://leeprecision.com/reloading-dies/rifle-dies/lee-deluxe-rifle-3-die-set). The Deluxe set includes a full length resizing die that allows
you to restore any case to factory original dimensions so that you can fire form
in your gun and then reload using the superior Collet neck sizing
die.

The
Lee Rifle Factory
crimp die (http://leeprecision.com/reloading-dies/rifle-dies/factory-crimp-die) is the only effective way to crimp bottle neck rifle
cartridges. This important step should be performed on all loads used for
hunting. Applying a Factory crimp will always improve the utility of the
cartridge and in most cases it will also improve the accuracy.

+what dougGuy said!

[rondog]

That's something I really should do, is designate a certain number of cases to each of my bolt rifles and keep them segregated. I just have so many bolt rifles and so much brass that it's a daunting task, but I think it would really be worthwhile in the long run as far as accuracy and shooting satisfaction are concerned.

[W.R.Buchanan]

Roger: I'm glad you have most all of this figured out and I applaud your efforts in actually trying to understand all the nuances.. Most don't.

The only small feature I would clarify with you is that the Lee FCD doesn't actually roll the crimp like a roll crimping die does.

It actually makes a flat crimp (see pic #1) which is generally placed in the Cannelure of the bullet. If there is no Cannelure then it simply does the same thing by impressing a flat crimp into the jacket of the bullet.

The First Picture below is a perfect Lee, Bottleneck Rifle Case, Factory Crimp on a .30-06 case ,,, made by me, just for your information. The Second is a Taper Crimp on a .45 ACP round and the Third Pic is of Roll Crimps on both Jacketed and Cast Boolits on .308 Win.

With these illustrations you can readily see the three different style of crimps used in their respective applications.

This was the only point in your write up above that I saw you might have some minor misunderstanding on.

The .45ACP round has the least noticeable Crimp however it is correct in every way for this cartridge as it measures .470 at the case mouth which is perfect.

This should clear it up for everyone. Clicking on the pics will blow them up for even finer detail.

Randy

[JWFilips]

All of my rifle brass is neck sized (after the fl sized case is blown out to that gun's chamber) Yes the Lee straight line seater does just that "Seats the boolits" On rifles I prefer no real crimp ( except for tube magazines) But even for them "Target off the bench" I do not crimp. But I prefer to run the "boolit seated" cartridge into the appropriate RCBS seater die (with the seater stem removed) to apply a very slight "Taper Crimp" just enough to remove the "Bell" from the expander on the case neck

[RogerDat]

Thanks W. R for the excellent pictures.

On the 30-06 the flat band is pretty clear, am I seeing a slight angle inward at the top of the case or is crimp actually flat top to bottom?

The .45 taper crimp to me just looks like a slight scuffing of the brass at the neck, possibly tool only contacted where the case was flared to keep from shaving the lead?

Roll crimp is the one I'm familiar with, also the one folks generally say is "best" for cast bullets. Especially if cast over sized. Lee however says their FCD that you show is (clearly) a flat crimp will work fine in that situation, will not reduce the bullet diameter while still providing a secure crimp if properly adjusted.

And thanks for the kind words, I can sometimes screw up even when I understand how it's supposed to work, lack of understanding pretty much guarantees screw ups in abundance. Wait I meant learning experiences not screw ups.

[W.R.Buchanan]

Roger: the picture is always slightly distorted. The crimp on the 06 case is flat.

The .45 ACP case is the most subtle. The cases typically measure about .473 at the base, and the crimp is only .468-.470. On the .45 ACP case the crimp is only about .030 long and that is why it is difficult to see in the pic.

A .44 Magnum case that has been Taper Crimped into the Tapered Crimp Groove of a cast boolit is much more prominent and shows up as the strait case wall abruptly Angling/Tapering into the Crimp Groove of the boolit. Typically in this application the crimp is about .040 long. It Looks basically like a strait angled version of a heavy Roll Crimp.

It does exactly the same thing as a roll crimp in that it pushes the case mouth, into the step on the boolit, stopping the boolit from being pushed into the case under recoil or whatever.

The Lee Rifle FCD does exactly the same type of crimp on a Cast Boolit as it does on a jacketed bullet,,, Except it usually doesn't look too good as the boolit really doesn't offer much resistance to the case and as a result it tends to just squish itself into the boolit. Not so bad if there is no crimp groove but pretty ugly if the boolit does have a crimp groove as the crimp just flows into the path of least resistance. IE: It ain't gonna look like that nice one on the 06 case above.

Best to just use the roll crimp on the .303 case with cast, and use the FCD on jacketed bullets. that's what I do.

Understanding this crimping thing is one of the keys to making really good ammo, and case prep is another.

Randy

[MT Chambers]

Couple of things here: The Lee Universal flaring die does nothing for case neck tension, both are important to get right. Proper and consistent case neck tension is important for top accuracy, crimping is NOT conducive to good accuracy and is only needed on big kickers, esp revolvers. Instead of worrying about crimp dies or collet dies, one should be more concerned about getting proper case neck tension.

[W.R.Buchanan]

NOE is currently making some really neato M Die style Expander Plugs that use the Lee Universal Expander Die Body.

All the Lee Die really does is bell the case mouth if used correctly, or stretch it badly if over done.

As stated above, if used correctly, it does not influence neck tension.

Randy

[EDG]

One thing no one mentioned is the use of the Lee FCD on cases that vary in length

The various roll crimp seaters will vary the amount of crimp when the length of the case varies.

The Lee FCD will give reasonably consistent crimp even when you allow your cases to vary in length some.

Most chambers are .020 to .040 longer than the max length of the brass.
I let the cases grow to minimize trimming. I do make sure they to not get so long they bind at the end of the chamber.
During the life of the brass the cases may get to the point that they vary a good bit - more than .010 or .015. When this happens there will be a small number of really long cases that get trimmed back to match the majority.
In this manner the Lee FCD cuts down on trimming chores for non critical ammo.

[W.R.Buchanan]

Good point EDG. And this is the main reason why I use one for all my .223 loading, as I usually shoot them and leave them.

I tried roll crimping first but the inconsistency in case length stopped me. The end result was a Lee die purchased to run on my D550B. Works perfectly !