Can I form brass using a neck sizing die?

[timspawn]

Can I form 338-06 from 30-06 using an RCBS 338-06 neck sizing die or do I need a full length resizing die? I do not own a 338-06 but do have the dies and am curious.

[EDG]

There is not really any forming to make this change. If you have a tapered expander in the die or buy one and install it it will open the neck up. That will make the case have the right neck but the body still needs to be sized using a FL die.

[BK7saum]

If the die has a tapered expander it will easily neck up to 338. However, there is no guarantee that the neck will be concentric to the body unless a full length die is used.

Brad

[BK7saum]

EDG,
I guess that we're in agreement.
Brad

[timspawn]

Thank you both.

[BK7saum]

It is possible that the neck expanded cases will chamber. If so then they can be fireformed.

I would personally try to expand using a FL sizer with tapered expander to get the best cases possible to start with.

[EDG]

You could FL resize fired cases. Then expand the neck and they might chamber. Like it says above the necks way not be concentric with the case body.
It is probably more practical to get the right dies for long term use.