Multiple Diameter M-Die

[jim4065]

Just day dreaming - does anyone make one? It would look kinda like a multi-diameter "step-drill" like you use for sheet metal. Start out with a .223 and keep steppin' up thru a series of little flats 'till you can seat a .458? Sounds practical to me - since larger diameter boolits tend to come in longer cases - but I'm sure not a machinist.

[garandsrus]

Jim,

Lee makes a "universal case expander" which will expand case mouths using a tapered expander. Not quite a "M" die, but it works well with most calibers.

John

[Jon K]

Jim,

What size are you looking for?
Lyman makes different size expanders for the "M" die, just call them and get the one you want, as long as the die length is OK.

You may also get custom expanders to fit your die from BA.

Jon

[ktw]

There is a set of articles on the Beartooth site about improving an M die with multiple diameter steps.
http://www.beartoothbullets.com/tech_notes/archive_tech_notes.htm/39
http://www.beartoothbullets.com/tech_notes/archive_tech_notes.htm/46

I would like to have one of these made up for my 38-55. I have a donor 40 caliber M Die for the project. Just haven't gotten around to finding someone to machine it for me yet.

-ktw

[Morgan Astorbilt]

These sound like the neck expanders I make for cartridge conversions. Get a 7/8-14 bolt, bring it to someone with a lathe, and let him turn the steps you need. Shouldn't cost much. If it wasn't 1:00am, I'd go down to the shop and take a few photos, and post them.
Morgan

[454PB]

I've posted this before, it's basically what Morgan was talking about. I treaded a piece of rod 7/8 X 14, then drilled a hole and installed an allen head set screw to secure each expander. It takes about 10 seconds to change the expanders. The nice part is that each expander can be custom made for the case neck.

http://img.photobucket.com/albums/v16/eddard49/Homemadeneckexpanders2.jpg

[felix]

I have Bonanza/Forester make the dies to my chamber of those guns which warrent such good work. The reason I have chosen these folks is because they do exactly what you want. Their dies automatically do what was spoken about in the Beartooth articles. We are talking about their BR die line, with straight line seating. For cast, there is no need to specify a micrometer seating die because each boolit will not exactly hold true to the setting anyway. You have too many boolit differences in cast, and is mainly hardness at the very top of the boolit which meets the top punch. If considering this approach, send them cases that have been reloaded several times with the load you have found that shoots best. Do not send them brand new cases that have been shot with only one powerful load. Use the cases you cherrish most for the load you are using. Tell them NOT to size the base of the case to anything below that what you have sent them. In other words, the fired cases must be 100 percent representative of your load. The only dies better would be those made by the smith who chambered your gun, using the reamers supplied to make commensurate HAND dies. ... felix

[NVcurmudgeon]

I use the RCBS case expander dies. IIRC, in .30 cal. there are .308, .309, .310 and .311 sizes. All other calibers give you a choice of one size. I've always wondered about how much difference an expander that is one or two thousandths "too tight" or "too loose" makes. It would probably take a bench rest rifle to determine.

[jim4065]

Really, I'm not looking for a specific size - more like wondering about possibilities. I have a desire, more than a need, for a multi diameter flaring tool (die, whatever.) It would replace all of the various diameter M-dies but still have a series of flats rather than the continuous taper seen in the Lee "Universal Case Expander". For example, this tool might start at .223, step up to .225, then another step to .243, then a step to .244, then a step to .255, then a step to .258 - - - - or what have you.

You get the idea - a series of short steps to act exactly like the M-dies, but for more than one caliber. Maybe 2 separate tools are required to run the gamut from .223 to .458? Maybe three tools are required to do it? Why do we need a dozen or more single step tools, or settle for a continuous taper which seems to be too "case length sensitive" (in my opinion).

Sorry that I'm not explaining this very well - or maybe it has no merit? Just a trial ballon.

[454PB]

The ones I made were made probably 25 years ago, long before the Lee universal expander or collet sizing dies were available. I have one of the Lee tools now. It's only shortfall is that it only flares the case mouth, and I wanted a tool that would actually open the neck to prevent deformation of the boolit. I use standard reloading dies for all my cast boolits, and they are designed for jacketed bullets. Resize a .308 Winchester, flare the case mouth, then seat a .311 cast boolit and you end up with a deformed boolit.

Your idea could be done, but in order to expand the neck area as well, the tool would have to be quite long for multiple calibers, and it's a lot easier to do one size at a time without risking damaging one of the "steps" and ruining the whole tool.