I read that you can use a regular .257 neck die to neck size for .257 AI and use the regular seating die to seat bullets. It makes sense to me as you are only sizing the neck and not touching the shoulder of the fire formed case. Thought I would ask before I get a Lee neck set and find out I wasted my money.

Does maybe help?? The answer is many of the various neck sizing only dies can be used as your are talking about. It depends on the design and clearance built into the die.

Why not spend the same $$ since you need to buy them anyway and get AI dies?

http://www.midwayusa.com/eproductpage.exe/showproduct?saleitemid=178014
If you want neck only just back the die off a little. Speaking as an owner of mostly improved style cases sooner or later you will need to bump the shoulder back.

If you are looking to use a Lee Collet die, then the answer is that the regular (i.e. non-AI) Collet die will work for the AI cases as well. I can't make a statement about regular NS dies in general.

In any event, for a low priced NS die, the Collet is the one you want. I personally tend to loose the Lee seaters which come with the Collet die set, but that is just me. I like the Forster seaters, so I normally get one of those.

Other than that, I agree with ramrod, that you'll also need a way to (at least occasionally) size your case bodies. In this case, a specific AI die will be called for. One option is to use your Collet die with a Redding Body Die - available from Lock Stock among other places...

- mike

I agree with mho and the others.

The only neck sizing dies I own are the Lee collet dies.

I sent 3 fired cases off to Lee, asking that they make me one of their collet neck sizing dies for my .223 Rem AI. They sent me a regular .223 Rem collet die, the difference in price, and an explanation that a special order die wasn't needed for AI cases.

I use my Redding FL 40 degree shoulder die to bump back the shoulder when needed, which isn't often with the straight sided AI case.

I also do the very same thing with my 338-06 AI cases.

Thanks guys I was planning to get the Lee collet die. I use the Lee collet die to resize my brass for .303 British also and love it.

What I do:

257RAI with sizer die backed off from the press, expander ball removed, make the forward 80% of the neck sized, but the part next to the should left as fire formed.