Home Forums Hunting & Shooting Ask The Gunwriters Lee collet die

Will a 243 win. collet die work for a 243 AI 40 degree case??

Not a writer, badger, but I don't think it will work. Those Lee Collet sizers follow the contour of the round pretty close.

I don't think there would be enough space to accommodate the fatter AI case body and steeper shoulder. I think you'd have to send them a sized case without primer with a seated bullet.

Last I heard, Lee had suspended making custom dies due to their backlogged shop schedule. Don't know about the current status of the custom shop.

I'd give them a call. Nice folks to work with.

DF

1) Measurement and math:
If I put a 0.500" pin gauge in a Lee 243 Lee collet neck die collet, it has 0.440" hanging out.
If I put a 0.350" pin gauge in a Lee 243 Lee collet neck die collet, it has 0.367" hanging out.

angle = inverse tangent = inverse tangent of rise over run= tan^-1 [.44 -.367]/[[.5-.350/2] = 44.2 degrees.

2)Kindergarten:
If I put some play dough on a 243 case and shove it in the collet, pull it out, and compare the dough shape to a 243 case and a 257 Roberts Ackley 40 degree, and take a picture.. the collet looks like it is greater than 40 degrees.

So, you think it may work?

DF

Both the kids in kindergarten AND college say it will work.

A Hornady Neck Sizing Die in 6mm Should work tho...

Just a guess, but as long as the shoulder-neck junction is the same, it MIGHT work.

Even if it doesn't, the collet should work for the initial loading before fire-forming. Lee stuff is so cheap it's worth a shot.

Mathematics has no place on this forum.

Playdough, on the other hand, fits right in.

Yeah, math touches too close to logic, for sure not a popular Fire commodity...

DF

Absolutely, indisputably, yes.

I use a Lee .243 collet die to neck size my .243 AI cases and it works perfectly. Surprisingly enough, it also works perfectly to neck size regular .243 cases.

And if you ever get a .250 Savage AI, you can modify a .257 Roberts neck die to handle those.

The collet die works off of the distance from base to neck/shoulder junction plus case length as a secondary consideration. As long as that first dimension stays the same, which it does in an AI case, the collet die works. There is plenty of room in the shoulder area for the blown out shoulder. The only one I would not be sure of would be when the original case has severely sloping shoulders like a .30-30 or .22 Hornet or .300 H&H.

FWIW, their factory crimp die will also work for cases of the same caliber and case length. It's just a big hollow tube with crimping fingers at the top.

https://www.24hourcampfire.com/ubbth..._Lee_Custom_Shop_suspends_pr#Post8865672

I had a 22-250Ackley,-- I had a standard 22-250 collet die. Once I adjusted it, it worked fine.

Absolutely will work. I use the standard Bob die on my Better Bob (as well as my standard Bobs) brass and the standard .280 Rem (7mm Exp) die on my 280 AI brass. They work beautifully... Without over working the brass, as those such as the Hornady mentioned above, will since they have expander buttons. They're better than standard neck sizers on concentricity for the same reason. Of course the fact that no lube is needed is reason enough for me to use them...

I swear by the Lee Collet Die and get one of every cartridge I can.

Expander buttons in and of themselves don't overwork the brass. Sizing it down more than necessary does that.

I use a regular 7mm08 on my 7mm08 improved. I have not tried it but I think with the correct spacer you could make it work on a .280. miles

Yes, it works. Just in case you skipped all the other posts in this thread

I don't disagree but it seems somewhat beside the point. I mean, isn't that what makes expander buttons necessary; the fact that the dies are designed to over size?

Otherwise why would an expander button be included in the design?

I also recognize this is necessary to contend with different neck thicknesses in brass, but the essential point remains. We're it not for over sizing an expander wouldn't be necessary.

Indeed it will, here is an article on the subject, Lee Collet dies used this way is discussed, look down the the later part of article. http://www.beartoothbullets.com/tech_notes/archive_tech_notes.htm/43

I do this with my 30-06AI, I have not needed to "bump" the shoulders yet.

italics added

I keyed my comment on that. It's a small point, I admit.

You're right.

There are several combinations that will work well. I've used a 6.5 Swede collet to size 6.5x54m/s. Doesn't quite make to the bottom of the neck of the 54 but close enough.