I am loading for a caliber that is not offered in a neck sizing die by any manufacturer (7.21 Firebird). Only full length sizing dies are available. I tried screwing the full length sizing die down until just the neck was sized. However, in order to get the neck sized almost down to the shoulder, the die needs to be screwed in until it touches the shellholder and then the shoulder is bumped back and the case is full length resized. Can someone explain the right way to do this? I know I have learned this in the past, but as I get older my CRS (can't remember shi*)disease get's worse. Thanks!

Just FL size it with the die set just right. This makes the best ammo for most rifles anyway. Don't worry about how far the necks are sized.

It's really not all that easy to get a die adjusted "just right". It's all too easy to size too much however. It's best to remove the firing pin from the bolt to get the best feel as you size a case a little more each time. The locking ring needs to be set and the set screw tighteded as well so this is time consuming.

Don't mix up shell holders afterwards either!

There's nothing that says you have to size the entire neck of the case. You can put powdered graphite
on your case neck, and back off the die until it doesn't touch the shoulder. Now take a look and see how
much of the neck you've actually sized. A quite visible ring will be present to indicate this. I neck size all
my cases, but only go about a third of the way down the neck. You're okay so long as the loaded round
isn't too long to work in your magazine. If your bullets are hard to seat you don't want them to be pushed
hard into the lands. Pressures go way up when it does. Best wishes.

I will answer your question with another question. Is there another cartridge that has the same neck size of the 7.21 firebird? You can use other dies to neck size that will not touch the body. I used to neck size .303 british with my 7.65 Argintine die. I guess I am telling you to think outside the box or the cartridge (grin) also sized the bullet length of 45/70 with a 45colt die. I used to neck size the 45colt with 45acp. It all worked. JB

As Savage99 indicated, the die must be set right. If you size all of the neck, you're going to also size the shoulder. Neck size a little at a time until you bump into the shoulder. Put some Prussian Blue on the shoulder area of the case (or mark with a Magic Marker) and it's very easy to see any contact points. This can be quite time consuming, but you'll only have to do it once. Then you can set the lock ring on your die. Like mentioned above, don't worry about resizing all of the neck. When sizing the neck, the only two things that are important are concentricity/runout, and consistent bullet grip sufficient to hold the bullet. If the case neck is concentric with the rest of the case and the axis of the bore, but you could use a little more bullet grip, polish the expander plug down incrementally until you achieve the desired purchase on the bullet.

As far as using a die intended for another cartridge for neck sizing, I think you can pretty much forget it. I don't know of any 7mm cartridge with a case as fat as the Lazzeroni that will allow the case to enter the die without sizing the case walls.

Easiest way I've found is to use the Redding Competition shellholder set. Use whichever one sizes the case the least -- try a few sized cases in your rifle to check.

In my .280 Rem. I can usually use the +.010" shellholder a few times. In my .375 H&H I can only use the +.002" or a standard one. My .338 Win. Mag. is somewhere in between, periodically needs the +.004" to allow easy chambering.

In my rifles, any setting that will give easy chambering will size the *outside* of the shoulder and at least a bit of the case walls. But you can do that and still get little to no shoulder setback, so the case will still be very tight in the chamber.

John

Lee will make up a Collet neck sizing die. A set costs about $50 however. If you like the rifle and it has a tight concentric chamber you might consider this.

I have modified Collet dies to neck size wildcats but I don't have the cartridge dimensions of that Lazzeroni.

Send three fired cases to Neil Jones and he will make you anything you want. He makes custom neck size dies with tailored neck/shoulder bushing designed to just neck size and bump.
http://www.neiljones.com/

Just use the magic marker and you'll be able to tell when the die touches the bottom of the neck or the shoulder. It doen't take any special dies or tools.

If you are trying to neck size only Cal said it right. "Step-size" the neck (though personnally I go about 3/4 the length of the neck on big game calibers). You better keep your ammo clean in the field though with unsized cases and watch neck thickness and case length.

But I find with calibers for anything bigger than varmints it's straining on a gnat for hunting ammo. Full length resize, bump the the shoulder .003-.005" for maximum reliability in the field. The big game hunting accuracy will be there if your rifle is capable.