LEE FCD die question?

p5200

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I'm using the lee fcd on my 44 mag loads of Hornady 240 gn. XTP over h110 powder. I've noticed after crimping, the COL seems to wind up a few thousandths shorter than before crimping am I using too much crimp causing this problem? Thanks! :)
 
When the die moves the case mouth into the bullet, the mouth edge curls back moving the bullet with it. The more the case mouth curls, the more bullets will set back.

Measure an empty case for length before then after crimping.
 
Measure case o.d. at case mouth. Exceseive crimp will cause a bulge and you will lose bullet tension.
 
If you find you need a really hard roll crimp and have the case bulging problem Rod47 mentioned, change to the Redding Profile Crimp die. It gets around that bulge problem by using a hybrid crimp shoulder that is a roll crimp at the top, but a taper crimp on the approach to the roll crimp. The taper hugs the sides below the roll, preventing that bulge.

The Lee CFCD (Carbide Factory Crimp Die, as opposed to the original FCD for rifle, which makes a collet crimp), has a carbide ring that is supposed to iron out severe bulging, but I doubt that works 100% for thinner cases. A Lee alternative is the Collet Style Crimp Die, which is available in 44 Magnum. Like the original FCD, it applies a collet crimp that will not shorten your COL. It does it with a funny collet with zig-zagging finger slots to get it short enough for the longer handgun cartridges.
 
Get the Lee Collet crimp die, they work great. I've been using mine for both .357 and .41 mag for a few years now and wouldn't use any thing else.
 
What difference does it make in regards to a "few thousandths" in a revolver?? It's not like they won"t chamber and a few thousandths wont spike pressures.
Over thinking it.
 
What difference does it make in regards to a "few thousandths" in a revolver?? It's not like they won"t chamber and a few thousandths wont spike pressures.
Over thinking it.
Come on, it was a good question. Reloading is a craft that involves some decimal places.
 
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I'm using the lee fcd on my 44 mag loads of Hornady 240 gn. XTP over h110 powder. I've noticed after crimping, the COL seems to wind up a few thousandths shorter than before crimping am I using too much crimp causing this problem? Thanks! :)
The COL change is normal - nothing to be concerned about. The FCD forms more brass into the crimp, and that shortens the COL. The FCD produces the strongest crimp, (with the least fiddling), I've tested - but neck tension is actually more important.
The FCD is practically mandatory when producing full power ammo for the lightweight S&W329PD.
 
Agreed. It's a good question, and the answer it this: it is of no concern, especially if the difference is consistent. No need to overthink. Load 'em up, shoot 'em, adjust as necessary, repeat and enjoy!
 
But "overthink" is a dismissive put down we don't need for a valid question.

I expect that if the bullet was seated a little deeper, the crimp could occur without having an angle for downward force on the bullet. The design of the particular crimp die would be in question...how exactly it achieves the roll. It is proper to expect that a seating depth carefully established would be preserved during crimp. However, the COL must be judged by the finished round +- a few thousandths for bullet irregularity.
 
While I generally don't like the term "overthinking" either, I think Don is correct that a few thousandths of COL variation in revolver ammunition is common and not very consequential because best revolver precision is generally lower than best rifle precision where bullet jump is an accuracy factor. The OP seemed to be concerned that the change in COL from crimping might be indicative of over-crimping. As has been explained to him, it is normal with a roll crimp.
 
I'd rather be shooting standing next to a guy who overthinks his loading process vs one who under thinks his process. Especially if that person is a relatively new loader and is seeking sound advice in order to be safe.
 
I suppose we have to distinguish between rethinking and overthinking. Rethinking is reviewing a checklist to see if you missed something and is always good to do at least once if not twice in reloading. Overthinking is applying Einstein's relativity equations to exterior ballistics where no result difference you can measure with reloading tools will be any different from those Newtonian mechanics provides (as is, in earthly experience, usually the case). I suppose, in that vein, overthinking might be arbitrarily defined as concerning yourself with anything resolving net random differences smaller than the finest measurement you can make. But sometimes you have to think a thing through to know the only difference you can make will be that small. But if by "overthinking" one means it just isn't worth bothering to consider, that's a call individuals have to make for themselves based on their interests and purposes.
 
I used the term overthinking things because of other posts and questions posed about reloading in general as to an example of trimming handgun brass because of a few .000 variations or the need to separate head-stamps for general plinking reloads
 
Choice of words being in question does not mean there were not good intentions. The OP sets the context for the level of detail in question. Referring to the premise as "overthinking" has the connotation of mocking the idea or the question, although may be making a useful point, if stated in respectful terms.

"Overthinking" seems like a way of saying "don't work at a level of detail greater than mine". Perfectionism may not make a practical difference but may provide satisfaction in thinking of ones work as high quality. It is personal in some regard. On the other hand, bringing a precision rifle mindset to handgun reloading may be a waste. Whatever. To me it is a matter of whether ammo looks right, spot checked under magnification, and fits in a cartridge gauge or in a chamber shorter than standard, lead bullet or otherwise. I know how to make that work. I refer to hand gun ammo.

It remains that if a COL changes from seating to finished round, something isn't exact in the crimp, although there could be very good ammo there regardless. Perhaps best to think of acceptable measurements as a working range. It can still be useful to understand what is happening in the process.

I only use an FCD for rounds culled from a gauge check and which do not provide any clues about what to fix. If still not gauging, I pull the bullets. I reduce the culling percentage by making sure my components are as uniform as possible. One particular culprit are lead bullets larger in diameter than expected. I do a lot more bullet sizing now, often finding a whole box .001 oversize and causing issues. Then suddenly everything is working.
 
I used the term overthinking things because of other posts and questions posed about reloading in general as to an example of trimming handgun brass because of a few .000 variations or the need to separate head-stamps for general plinking reloads
Personally, I don't reload with any different attention to detail for a given application. It's all as good as I know how to make it. High volume reloading is often for competition, so one does not have a casual attitude toward quality. I will say though that cowboy loading is not so detailed when NOT crimping in a groove, using 38 Special cases in a .357 Mag rifle. COL is the measurement of concern, so many can use unmeasured, mixed head stamps without any problems. I don't know if they avoid names known for thick rims or thin case walls (loose bullets), but I sort head stamps for that. I also have Winchester brass in 38 Special that doesn't always fit in a particular brand of shell holder, forcing me to sort head stamps. Loading .357 Magnum on my Hornady LnL AP without a shell holder involved allows freely mixing Winchester and Starline. I quickly learned that other head stamps needed to kept out of the mix.

All that is revolver related, which may not apply equally to semi-auto reloading. My 45 ACP is a story in itself. Same for 9 mm or 40 S&W.
 
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