Hi,

I need a favor. If anyone has this die, could you tell me the resulting base and shoulder diameters, following sizing? I'm going to have a reamer made, and want the case to be sized just a hair under the chamber's dimension. Thanks in advance.

Ralph

Hey Ralph, Don't think of this as negative input, because it isn't intended that way.

When they make the Redding Dies(or anyone does), they have a Tolerance of " + or - " some amount for all the Dimensions. The Tolerance Range from one end to the other is very small, but it has to exist or they could not stay in business.

The Cases are all slightly different in their Composition and in their degree of Annealing. As the Case is Resized and withdrawn, it "springs-back" a tiny amount, so the dimension you would get is actually different from the inside of the Die - not much but some.

You would need a Cerosafe Cast of the Die in order to get what you are looking for. But it isn't perfect either because it "shrinks" tiny amounts over time.

I understand you want as close a fit as possible between the Chamber and Resizing Die. My suggestion would be to talk to the Reamer folks, explain what you are trying to do and see if they can't give you the information you are looking for. They may even know someone who is already Set-Up to cut your Chamber and a set of Custom Dies to match it for you.

Best of luck to you.

I understand what you're saying. I guess I can always lap he die in with a fired case. Still, can you please share this top secret info just so I can have an idea?

I'm worrying that it will reduce the shoulder diameter by .005" or more and I don't want that. The shoulder diameter on the 223 Ackley should be .370" approximately, right?

I think it sounds like an excellent idea. If you are going to have the reamer ground anyway, it would be perfect to have chamber and die match (chamber about .001-.002" larger than die) on the dimensions that matter.

It is probably true that dies might vary from specimen to specimen. In that case, buy your die up front, and have a cast made, and measurements taken just after the cast has been removed. That way you can minimize the effects of the shrinking cast over time.

Alternatively, you could have your reamer ground according to the size of new brass you'd like to use - Winchester or Lapua, say. Once the rifle has been chambered, fire a couple of shells, and send them plus the body die to Jim Carstensen (see: 6mmBR Article about JLC), or Neil Jones (www.neiljones.com) and have a die made, which will fit your chamber. I'm not exactly sure if they work on all caliber dies, but it would be worth asking about your specific caliber...

As Hot Core suggested, it might also be a great idea to talk to the reamer manufacturers, and sound them out on the right dimensions. Most likely somebody will already have done what you are planning.

Also, if you intend to use a Redding Competition Seater, it might be worth figuring out the internal diameter of the case supporting sleeve. I have run into factory chambers, large enough to have the case body sized (minimally) by this sleeve.

- mike