Factory Crimp Die -or- NOT

[mpmarty]

I use the FCD on my 45/70 cast bullet loads, on my 7.62 Nato and 30/284 (7.5X55 Swiss) when the bullets have cannelures. I took one look at the FCD for straight wall pistol dies and just laughed. Yea, sure I want to squeeze my bullets down undersize so they will lead the barrel evenly and thickly. NOT! Post sizing is the answer to a question nobody in their right mind ever asks.

 

[BullitHolz]

We talked this subject to death over on the ruger forum a while back and it yeilded someinteresting results.

First of all the issue with the Lee dies is NOT with the FCD, it's with the sizer dies. Basically they are ground to size the cases about 1-2 thou larger than other manufacturers dies are. I measured mine and so did a few other members and we all found we had the same dimensions for a given caliber.

So, on to the problem....
If you size your brass with Lee sizers it will be sized "loose", consequently it would seem that the Lee folks want you to use their FCD to "final size" the brass to specs at the last station in the reloading process.

in most situations this isn't an issue and most guys using their dies will never be aware of the dimensional differences. Sometimes it DOES have a noticeable difference. Case in point...Remington brass is thin, so thin that it will pass through the FCD with zero drag, no huge deal there really. That same brass when sized in the Lee full length sizer will often not be sized down enough to provide adequate neck tension of the bullet, in some situation there is actually NO tension at all and the bullet can be dropped into the case and hit the bottom. I noticed this with my .357/.38SPL reloads using the Lee 4 die set.

Thicker brass like Winchester seems to work fine and the added wall thickness decreases the i.d. which hold the bullet in the neck adequately. Winchester brass also will drag through the FCD every time which is yet another benefit of having a thicker wall.

I got really curious and picked up a set of RCBS dies and tried using the RCBS sizer in my reloading and the results were surprising to say the least. After sizing the brass with the LEE die and pressing in a jacketed bullet the "bulge" that usually shows up in the case walls where the base of the bullet sits in the brass was barely visible, indicating a potential for loose neck tension in the loaded round.

I did the same experiment using the RCBS does and noted that the bulge in the cases was very pronounced once the bullet was seated in the case, hence VERY good neck tension was apparent when using the RCBS dies. As a result of the increase in neck tension my handloads shot 1" smaller groups from my GP100 at the very next range session.

So, what do I use now for dies? I do not use the Lee sizer dies anymore but I do like to use the FCD as a final step. My reasoning is this, every so often I'll get a case that will not glide through the FCD and those are the ones that get a hard second look, sort of a final QC check of sorts.

Oh and one last bit of advice, DO NOT use the Lee die sets with lead bullets, especially the FCD as it will undersize your bullets in the cases, especially if your using the thicker brass like Winchester. Of course you want lead bullets to be larger than the bore by 1-2 thou and by using the Lee FCD you'll actually be sizing the bullet down to bore size, reducing your bullet to bore seal and increasing leading and decreasing accuracy.

 

[Redneck with a 40]

Bullit, that makes sense, when I size my once fired brass that I buy at gun show's in .308, with the Lee sizer, it won't chamber worth a damn in my SPS Tactical, which has a tight chamber anyway. I bought a RCBS small base die and now they chamber like butter. The Lee doesn't and won't size the cases small enough. I'd probably be fine for a semi-auto (loose chamber), but not for my bolt gun.

 

[russ45]

For pistol cartridges, I find that it is easier to get the right roll crimp for revolver cartridges using the FCD, but for taper crimp on 45 ACP it it not necessary and crimping in the seating die works just fine with one less step.

 

[Slamfire]

I bought a RCBS small base die and now they chamber like butter. The Lee doesn't and won't size the cases small enough. I'd probably be fine for a semi-auto (loose chamber), but not for my bolt gun

.
You know there are people on this site who would, in some many words, call you a liar. They state emphatically that no one needs small base dies, because they have never needed a small base die.

As for the statement that semi autos come with big chambers: not all. The truth of the matter is small base dies will improve function in many semi's. If the case is an interference fit in the chamber, the rifle will either jam on feed, or jam on extraction. A case swaged into the chamber will darn near weld to the chamber case walls after ignition.

(Oversized reloads and the subsequent complaints have induced some barrel makers to cut their chambers large. Soon we will be stuffing sausage sized cases into Zeppelin sized chambers!)

Still, a small base die will oversize the case if the dies are not set up with case gages. And it is virtually impossible to small base size a case with spray on lubricants. I used RCBS water soluble or Imperial sizing wax.

 

[Marlin 45 carbine]

I use the FCD for pistol rounds - myself I think it's worth the trouble.
I use it for a LIGHT crimp on rifle rounds w/o cannelure also. I don't shoot a lot of rifle anyway so it's no trouble, the extra step I mean.

 

[sig2009]

I will never load another round without one!

 

[TeamRush]

Not 'Scientific' by any means, but my 30+ years of reloading experience says that factory crimp dies help out my autoloaders a bunch.

I DO NOT use it on any of my NON-Autoloaders.
No real sense to seeing as I've never had a problem without the FCD, why start crimping now?

On the OTHER HAND,
I purchased the factory crimp die to stop a particular problme in my autoloaders...

The RCBS dies I was using had a crimp built into them, and any variance in case length at all would screw up the crimp/shoulder of the case.

The FCD allows me to seat the bullet properly,
THEN apply a crimp to my Auto Feed ammo to keep the bullet in place through 'Rough' cycling (Like AR-15's!)

And since 9mm Semi-Autos, AR-15 & AR-10 rifles are about the only ones I ever had a problem with,
Those are the ones I use factory crimp on.... Problem solved!

My bolt rifles, lever guns, revolvers, ect. have never needed a 'Factory Crimp', so I STILL to this day don't use a FCD on them...
--------------------------------

Now, Bench rifle guys have noticed you can change the muzzle velocity (very slightly) by using a hard factory crimp,
But the brass doesn't last NEARLY as long if you do!
(ask me how I know that! )

 

[MMCSRET]

Whether or not I use a FCD or a CCD(handgun) depends on the cases, bullets and firearm. It does not depend on my opinion of the die itself, Lee Precision, or anyone else's opinion. I have them for every cartridge I load and use them as needed. Good tool, to be used as needed. Like every other tool it does not fit every application.

 

[rcmodel]

lever guns, revolvers, ect. have never needed a 'Factory Crimp'

Say What?

You mean the factories have been doing it wrong for 150 years?

Lever-gun loads should always be crimped to prevent bullet set-back from recoil in tube magazines.

Revolver loads (above mouse fart level) should be crimped to prevent recoil pulling the bullets out of the cases.

rc

 

[Asherdan]

I use 'em and like 'em fine in handgun and my lever rifles. Had a little merry-go-round last year with cast in 44 mag and the carbide post sizing ring on the FCD. It wanted to turn my .431 cast into .4295 and that didn't work for my carbine barrel. Called 'em up and ordered a second one for cast loading and had 'em open it up by .002, end of problem. In 45-70 the FCD let's me crimp cast independent of the cannellure position.

I'm going to echo the sentiments from another post, it ain't a cure all for everything, but it fits some needs well.

Joe over at Real Guns has had some interesting articles that discuss the Lee FCD's, may be worth some time.

 

[remingtondude58]

I always use a factory crimp die. I never have had any problems. Even the couple of times I did not push the case all the way into the shell holder, and but a big bulge in their; The die sized it back to normal.

 

[Walkalong]

It sized it back, but not to normal.

 

[P97]

When I started using the FCD on my Auto Cartridges, I stopped having feeding and ejection problems. Since I don't want to load for individual guns, I use it on all mine. It works fine for me, and all my reloads work in all my guns.

 

[P97]

Double Post