Lyman m die

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lonewolf5347

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I like to ask has anyone seem to get better accurate cast bullet to fly when using the lyman M die.
I been using the m die in my 9 mm reloads seem a toss up between the Lee powder drop expander die.
I find the only problem is I need to set up a single die taper crimp die separately
More time then trouble.
 
Lyman M dies were the first that created a step for the bullet to sit on. Now Redding and Dillon dies have the same type of seating stem. If you are using an oversized bullet, you have to open the case in order to prevent shaving or swagging the bullet back to a smaller diameter. That's why these seating stems where designed this way. The shelf that is created fr the bullet to sit on also helps to keep it straighter as it is seated into the case. NOE actually makes several diameter seating plugs for each caliber depending on the diameter of the bullet you are seating.

If you are loading standard size plated or FMJ 9mm bullets, the M die probably isn't necessary. If you are loading oversized lead bullets, its essential to get the best accuracy.
 
I put a 38s&W expander in my 9mm lee die. same effect, a lot cheaper.
and yes, my .358 diameter oversized bullets fly a lot straighter than without it.
 
been using the M dies in 9mm, 45ACP, 38/357 for years
and for those who headspace on the mouth use taper
crimp dies, use a lot of cast bullets so it works the best
have used others but go back to the M dies, an old tyme
reloader here, tried a many of thing in the years....
some work great, others not soo great.... still use
Hornady Pro7's, Projectors ( pre LNL ) one in 9mm
38/357, 45LC, all with the M-dies, not trying to set any
records, plus my reloading is R&R time not a J.O.B.

-Snoopz
 
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I can not get my .303 rounds, in straight, without it. The rounds wobbled when rolled, badly.
 
I have made an arrangement to load cast bullets in 308 using a Lee four hole turret press. The expander plug from NOE fits into the Lee expander die body. These plugs can be ordered by size. For example, I ordered .309, .310 and .311 to expand 308 case mouths. Used gently, an FCD was used to assure none of the expanded case mouth remained. Using the NOE parts make for more flexibility than with the M die.
 
My 'M' die use:
Bought the 30 cal M die for 30-30/.308 and used as such.

Here recently, I have been working up a 300 BlackOut load with this same 123-124gr. Gas checked RN projectile.
The original outer die housing was too long to reach the BO case for proper expansion.
Used a spare RCBS .45acp expanding die housing to hold the Lyman center assembly to be able to open the 300 BO case. Works well..Bill.
 
M die bodies: OK, I'm mouthy this morning. Procrastinating getting ready for church. There are two bodies for M dies. Unless there had been a change a long and a short body. Seem like they were marked M-1 and M-2. The short body, for handguns and the like, would work-probably. The Lee Universal expander die may be a less expensive alternative to getting another M die or M die body.
 
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I use an M-die for every caliber I load for. Yes, its an additional expense, but well worth it to avoid the hassle of trying to either set a generic pistol expander correctly, or trying to seat flat based bullets for rifle. Ive also found that that when I wet tumble you will get an occasional case with an out of round mount, the M-Die will fix that without over expanding the case mouth.

As others have pointed out, there are copies of it made, and even some are PTX.
 
My experience: The M die is oversold for expanding or ironing out case mouths. The Lee universal works well when you start newly casting for calibers with no expander die. Adjusting expanding dies is no big deal. Making this stuff sound like brain surgery is a real trip. Finding plugs for every caliber can be hard. The Lee works very well. Expanders have been this way, the M die; since the the dawn of time. There's no copying involved. My experience with M dies is recent like for the past forty years. You can goof up a case mouth with an M die just like any other expander.
 
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The M-Die was different and they did copy it recently. RCBS and Redding both changed their expanders to the M-Die type expander. In other words, a parallel second step instead of a flare. They do still have a flare for a third step now if you run the expander in enough, but it isn't very practical.
 
You are certainly entitled to your opinion. I don't think we need to add copy to the censured word list quite yet though.

I would like to hear some more opinions on this. :)
 
Expanders have been this way, the M die; since the the dawn of time. There's no copying involved.
Perhaps I'm misunderstanding what you mean here.

Are you stating that:
1. other expanders have always had the same parallel sides that form a "cup" in the case mouth like the M die?
2. RCBS and Redding didn't recently change their expansion dies to the "M die" form?
3. the NOE expanders for the Lee expansion dies do not use a different form than the factory expansion dies? http://noebulletmolds.com/NV/index.php?cPath=565_89
 
This is my opinion based on my experience. Expander plug use had been a minor hot button topic on and off for years. Look, if you think the M die was a reloading miracle have at it. I went into my Skunk Works and checked out an Ideal marked set of 310 dies for 257 Roberts-maybe sixty- or seventy years old. The expander worked exactly like today's M dies. It's simply another way to make an expander plug. I learned using an M die to load jacketed bullets is a non-event. Been there and done that. Using the NOE plugs gave me much more control seating my lead bullets in 308-knowing major and minor dimensions of the stem. Goggle expander mandrels. If you want concentric case necks check out neck turning. Look into your M die for the precision fit of the body with stem and your case. I use expanders, including M dies, to prepare case necks for lead bullets. That's what they are designed for. Like I say, if it works for you do not change your techniques. Seriously.

Addendum: Would a Lee Collet die or FL die work better than an expander plug down the neck for jacketed bullets.
 
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What is good for the lead goose, is good for the jacketed gander, too.

I don't like the way the M-type expanders shave a bit of brass at the mouth when the cases are new, though it could have just been mine. The slight step does make situating a bullet easier. It can be over done, however, everything can be over done.
My preference is toward a standard bell shape. Admittedly, I have only used one stepped expander, but the experience was not bad.
 
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