M type expander

Pistolero

Pistolero

Well-Known Member
I would like to make a .30 cal M-type expander, but not sure of dimensions. If someone could
give me the initial diameter, then the diameter of the step, and the length of the initial expander
portion, I would appreciate it. Please measure with a micrometer, not a caliper.

I assume that the expander leaves a couple of thousandths of interference fit. Since I use .311
to .310 for my .30 cals, then I guess something like .308 or .309.....but there will be some
springback, too, I think. I think the step is actually larger than the bullet, so maybe that
needs to be .313 or .314? I could try all this, but copying one that works well should be
quicker at getting there.

Thanks.

Bill
 
JWFilips

JWFilips

Well-Known Member
Pistolero,
My custom one is .002 under bullet dia on the lower For me that is .309 The next step is .312" with slight .313" taper for a .311 bullet
Buckshot did mine ...Works great and if you need it for a .310 just don't run the case up as much
 
Rick

Rick

Moderator
Staff member
I have the Lyman M die in 30, no micrometer or caliper but I do have a tape measure.

Ok, just jerkin your chain. I'll try to get to the shop tomorrow and see if the battery is not dead in the mic.
 
Brad

Brad

Benevolent Overlord and site owner
Staff member
I get .306 and .311
Smaller than I expected. There is also a slight flare on the very top of the larger step that can flare the case mouth to prevent shaving lead.
 
RicinYakima

RicinYakima

High Steppes of Eastern Washington
30/06 FA cases, stress relieved, will spring back about 0.001". For match work I made it 0.001" smaller than bullet, and initial portion is full length of the neck so it does the whole length. Top is just a 15 degree included angle up to thread size. HTH, Ric
 
Brad

Brad

Benevolent Overlord and site owner
Staff member
I like Ric's design. Minimal neck tension, but enough to handle the ammo.
I suppose some depends on the end use. More tension is good for a lever action but a bolt gun fed single rounds don't need heavy neck tension.

Bill, you have the lathe, make a few and see what works best! It's only time.
 
Ian

Ian

Notorious member
+1 on Ric's design. I personally refuse to use the stepped expander spuds for a multitude of reasons. General rule for me is thick brass .0313-.-315" pick an expander that is bullet size to a thousandth over, and with thin brass common to things like .30-30, I go right at bullet size or maybe a thousandth under, depending on what shoots best with the load I'm using. What's important to note here is that I resize my necks a minimum amount using either full-length resizing dies with the necks enlarged, or use resizing dies with selectable neck bushings, so there is very little spring-back involved with the "expanding" operation. More or less I just use exanders to bell the case mouth and ensure uniformity of the whole neck.
 
I

Intheshop

Banned
They're pretty easy to make,once you determine what dimensions (covered above)....make a cpl.Make the first section long enough to give good purchase,and alignment for holding in chuck whilst threading.

Goals for me are; repeatability (lathe settings),finish(predicted polished diam reduction,along with tool "bit"),how fast(money) they can be made which is a convenience thing....hard to put numbers on which is why its part of the criteria.If it's gonna take all day....order one.

Threading is easy for me.....ridiculously so,making it not really a goal.

PS,pay attention to the degree of finish/polish.Don't assume a few tooling marks are "bad",think about it.Good luck,BW
 
JWFilips

JWFilips

Well-Known Member
Brad said:
I get .306 and .311
Smaller than I expected. There is also a slight flare on the very top of the larger step that can flare the case mouth to prevent shaving lead.
Click to expand...

Brad if that is the Stock Lyman expander it is for Jacketed
I think lyman makes a stock .312" mandril For the 303 Brit That may work well for you Bill
 
Brad

Brad

Benevolent Overlord and site owner
Staff member
Mine is the stock 30R expander. Definitely designed for jacketed. Works well for much of my needs but then again I never played with it very much. Less neck tension may well help in some rifles where feeding from the magazine isn't an issue.
 
KHornet

KHornet

Well-Known Member
I use the expander inserts that Al Nelson makes for use in the Lee expander die.
Have one for each cal I load. They work super well.

Paul
 
quicksylver

quicksylver

Well-Known Member
Missionary said:
Those NOE expanders are the Best ! That was one of the brighter moments in my reloading decisions.
Click to expand...

Almost the same for me...I bought 4 and have been using them..my only criticism is that they are just a tad too short for 30-30 and 30-06... I called Al about getting them made longer ,he told me that he would speak to the person he subs those out to...
 
quicksylver

quicksylver

Well-Known Member
Forgot to mention...like Ben I use the next larger size when I am loading Plain Base bullets..
Gas checked 30 cals with Mil brass and a .311 bullet I use .308 or.309 ....309 for plain base..
your alloy will also determine the best size...
 
J

JSH

Active Member
Bill,have you given any thoughts to buttons. Though you would still need to flare/bell case mouths a bit.
 
P

popper

Well-Known Member
31R for 30/30. Lee flare tool as I don't trim cases. Blue locktite on the threads. Had a 41M spud cut down for 40SW, use a carbide cutter.
 
Pistolero

Pistolero

Well-Known Member
YIKES! Thanks everyone. A lot to digest.

Maybe too much info. Yes, Brad, I want the info to make one, but was hoping not to make 3 or 10 before I found a good
combo. :)

Brad - AFAIK, the sole purpose of the M-die is for loading cast....so you say yours is "definitely for jacketed"?:confused: Is that
a Lyman M die or just a regular expanding button?

I think I will try for JWFilips 31R based on his great photo with nice detailed dimensions. Thank you so much, sir. Nicely
done!

Sounds like I wasn't far off just using the Lee Universal Flare tool until now! I will start with the 31R dimensions and
see how it goes.

Guess it is OK to drift my own thread. :rolleyes:

Looking for new lathe projects. Just made an oversized firing pin for my Kel-Tec PF9. I was getting a bit of primer flow
into the annulus between FP and breech face hole on some reloads, but it was inconsistent. The original FP was
.069 at the tip, breech face hole takes a .078 pin gage, so I made one with .075 tip. Pops primed cases in the
basement fine, will try some live ammo tomorrow. It was shaving little slivers of brass and would eventually jam the FP
and misfire.....GRR. Loads are below max, and dropping down didn't help and the original higher load has been used
in about 7 other 9mms for several years with not a hint of problems, so I think it just has to be too much clearance.

We'll see. A bit of a PITA to machine, 1.621" long and max diam is 0.155, first .550 is
only 0.075, then tapers up to .112 at 0.915 from the tip, so really whippy, cut it in steps. Had to mill a
retention cutout after turning. Loving the new lathe.

Next is new one piece FP for darned beautiful Win 1886 Extra Lite with insane, horrible, garbage, stupid,
worthless, junk three piece firing pin with internal locking latch.......WHAT A POS! in a gorgeous, beautifully
crafted and finished rifle. Misfiring and vertical stringing of up to 18" (by 3") at 100 yds has been no fun at all. Reduced
the rebound and refitted, retimed the FP latch and it is better, but it really needs a one piece FP. And OF COURSE
an original 1886 Win FP will not fit, (bought one) they planned it that way. So, I will make one from scratch, darn their
lousy lawyer hides. Anybody need an original 1886 Win FP, mint, never installed?

Considering cutting off the rear 1/3 and drilling and tapping, putting a new rear 1/3 on with
red Loctite.

Bill
 
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