M die question

Petrol & Powder

Well-Known Member
Ian, I don’t believe your personal views on this will result in a great schism of the reloading world. To each his own.

The expander you show will get the job done.

I’ve never seen a “M” die expander harm the case mouth unless it was grossly misadjusted. And the benefits that Snakeoil listed are in the positive column. Particularly the creation of that “socket” feature on the case mouth.

Now, with that out of the way, I will say that on a bottleneck casing the depth that the expander spud enters the casing is a lot less critical than on a straight wall casing. So, if you’re dealing with a bottle neck case and you don’t care if the entire neck is expanded to a desired diameter, the distance between the tip of the expander and the beginning of that flare isn’t as critical. This may be where some of the dissension rests.
 

popper

Well-Known Member
Didn't say the M die did it, saying the M die doesn't remove it. The rotational movement of the pliers does. Haven't reloaded any 308 for a while but I will check when I do.
 
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Snakeoil

Well-Known Member
I tried to take a photo of the M-die plug I made yesterday for a shooter at the club. But even with Macro, it's tough to distinguish the step. So, made this quick sketch. These dimensions were driven by a specific application for another shooter. I do not use an expander plug since I feel it overworks the brass. The Lee collet die gives me what I need for neck tension. I size what I call the guide portion of the plug to be the same or slightly under the sized neck ID. I actually made up my collet die with parts from .303 Brit to size the neck for my 0.314 bullet diameter.

So here is the sketch for the M-die plug. This is for use in loading .308 and .30-06. How the plug looks to the right of the step in the picture is determined by the config of the die it goes into. In the case of this one, it was left at 0.375 diameter with a 90 deg step at the end of the 0.100 long step. This was per the recipient. He sets his up by taking the longest case in the lot and adjusting the die so the case mouth just kisses that step and then backs it off a hair.

M-die.jpg
 
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Snakeoil

Well-Known Member
Since we are on a roll here, I'd like to add another entry to my list of M-die advantages.

5. It allows for a slight variation in OAL without altering the effectiveness.

By this I mean if you use a tool to bellmouth the case, the OAL of the case will affect how much of a bell you actually put into the neck. The deeper the bell, the wider the bell and the more stress on the case mouth. Where with an M-die, all you are doing is slightly increasing or decreasing the depth of the socket.

Sumpthin' tells me that discussions like this are akin to oil threads on motorhead sites. Consensus is just a pipedream.;)
 
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Snakeoil

Well-Known Member
The one consensus I think we can reach is we all have what we like and reasons for it, and as long as it's working for us then...it just works.
There ya go. That's the right attitude about pretty much life in general. Some like fat ones, some like skinny ones, right? Who's to say which is wrong and which is right?

The nice thing about discussions like this is a new guy can sit back and listen to the dialogue and make an informed decision on the path he wants to take. That, I think is the true benefit to offering up "this is how I do it" in places like this.
 
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fiver

Well-Known Member
guess i get to say it again.
i got nuthin, as in I have no flair or step type dies.
i guess that ain't exactly true, the Dillons have a thingy that lets the powder go in the cases it flairs the case mouth.
 

Snakeoil

Well-Known Member
guess i get to say it again.
i got nuthin, as in I have no flair or step type dies.
i guess that ain't exactly true, the Dillons have a thingy that lets the powder go in the cases it flairs the case mouth.
Progressive presses are normally for pistol caliber and rifles that go thru a lot of ammo and they are usually military calibers where cost is low. A flare is needed or you'd be crushing more cases than loading cartridges. I'm sure there are folks here that use a progressive press to load one at a time, but for the most part, they are for spittin' out ammo like poop from a goose.

You know, somebody should load some bench rest ammo with a progressive press, using it as a progressive press, not one at a time. And then put it thru the same rifle along with some carefully, anal retentive bench rest loads to see how they compare. I suspect it might put a few myths to bed.
 

RicinYakima

High Steppes of Eastern Washington
You know, somebody should load some bench rest ammo with a progressive press, using it as a progressive press, not one at a time. And then put it thru the same rifle along with some carefully, anal retentive bench rest loads to see how they compare. I suspect it might put a few myths to bed.
For pistol ammo, that was done with the RCBS "Green Machine" in the 1980's. Progressives could make as good of ammo as the best single stage if you didn't try to adjust it. I seem to remember it being published in Precision Shooting or Rifle.

By the late 1990's Dillon's would load ammo good enough for most NRA high power shooting in 223. That only requires one MOA, but to get down to 1/10 MOA you have to have better dies and presses. That is the reason Harrell's and Hall presses are still made and LE Wilson dies are sold to BR shooters.
 

Petrol & Powder

Well-Known Member
I hesitate to get into the progressive v. single stage arena but here goes...

Progressive presses are easily capable of producing quality handgun ammo, and that is where the progressive presses shine. I have no desire to load 500 rounds of handgun ammo on a single stage press and pull the press handle 1500 times (or 2000 times if I'm seating and crimping in separate operations).
With the right gear and attention to detail, a good progressive press can produce amazingly consistent ammunition. That doesn't mean every person with a progressive press will accomplish good results, it just means good results are possible. There's a difference.

I load rifle cartridges on a single stage press but I'm not dealing with the same number of rounds per session when loading rifle cartridges. Again, good gear and attention to detail can (not absolutely will) produce excellent results.

I will say that the powder funnels (Dillon's name for their powder through expanders) are NOT well suited for cast bullets. They are configured for jacketed bullets (too small and they do not have the "M" die profile). Fortunately, this is easy to remedy. Custom powder funnels are available or can be fabricated.
 

RicinYakima

High Steppes of Eastern Washington
It is not "progressive" vs "single stage", but how straight and square are the presses and dies? How close do the threads of dies and presses match? It is not that a progressive press can't be built to those specifications, but who wants to pay the multiple thousands of dollars for a faster press when you can load 60 rounds a week at home or at the range?
 

Petrol & Powder

Well-Known Member
I think progressive presses can have rams, shell plates, tool heads and other parts with sufficient squareness and tight enough tolerances to make ammunition well enough.
The fit between a case head and a shell holder has more slop in it than all of the other interfaces put together and yet we still manage to make fine ammo.
The threads between the die body and press need to be good but not perfect. The dies need to be held fairly straight; the threads need to be cut OK but we're not talking about micrometer threads here.
Most rams are more than square enough to the die to make that relationship non-critical.
I'm sure one could find dies with bores that were not concentric to the dis body but most of them are true enough.

I'm not saying that tolerances and good alignment aren't important, but I do think we get a little too excited about extreme precision sometimes.
 
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fiver

Well-Known Member
Dillon's powder dumps don't even use the funnel/flair thing for rifle cases, they use a little collar similar to the bottom of a powder dump.
and yeah i've loaded a grundle of cast bullets in rifle cases for stuff with one.
never really tried them against a different press for absolute accuracy though.
i don't even use it for the most accurate load, it's more for getting a can full of ammo today with a close nuff load.
an inch or so is good enough for most of my rifles.
 

CZ93X62

Official forum enigma
I use both RCBS-type expander/flaring spuds and Lyman-type M-dies. Now having seen the Lee Universal Expander Die with the NOE spud attachments, some of those may be added for some calibers. THANK YOU for the heads-up.
 

358156 hp

At large, whereabouts unknown.
I'm currently running three different presses. A Lyman T-Mag II that I use for case prep and general non-critical tasks like cast bullet sizing. My newly repaired Redding Big Boss for most rifle loading, and a Dillon 550 for production work.