Lyman M Dies and Case Life

[newfoundlander]

Last night a friend of mine who is getting ready to load his first ever batch of CB's (303 British) asked whether or not the Lyman M Die will adversely affect case life. He already has a set of Lyman dies that came with the appropriate M Die so he's not really looking to replace it with something like a Lee Universal Expander unless it's warranted. I've never had a need for a dedicated neck expander/belling die as I ream/ turn all of my necks and use Vickerman type seating dies.

[felix]

A case wears every time it is contracted and expanded via tools or gun. The wear is on the internal level rather than on the external level. Annealing will take care of this "internal" wear, and the case should last forever per this kind of application. The more accurate the gun, the more accurate the annealing is required. BR folks in the condom world typically trash the cases which shoot out of the group (for any reason). ... felix

[sundog]

Noofie (that's a term of endearment, not a slur), I happen to know something about this as I am currently in process of .303 testing and shooting a mil bolt match for record (tomorrow). My fire formed cases were neck sized with a Lee collet neck sizer. GCs are standard 30 cal Hornady. My boolit is the Fatter 30 group buy run through a lapped out Lyman .314. Finshed boolit is .316+.

But, here's the BUT. The gas check is sized only on it's forward portion. Being a .30 GC the base is small enough to start in the neck sized case to about the point where it contacted the boolit sizing die. Once seated there is an ever so slight ring of lube (FWFL) around the case mouth which is simply swiped over the boolit with the fingers. Many have almost none.

Unlike JoeB, who espouses that case mouths MUST be belled always (another thread), I simply do not need it in this case (or many others, e.g., the SAECO #301 in an '06 case with Gator checks). If you don't need a bell, DON'T.

Sometimes a light twist of a needle nose plier is all that's needed to get a boolit started. If the inside of the case mouth is rough, a light twist with an inside chamfer tool can also help.

[Char-Gar]

The M die won't be as harmful (in terms of care life) as draging an expander ball through the sized neck. I remove the expander ball/plug from the sizing die and them use an M die.

Unless you have ultra rare case that can't be replaced, then brass life for most rifles is a very minor consideration. Neck sized cases, expanded with an M die, fired in a good bolt gun will give as much case life any anyone could reasonably expect or want.

Of course there are better ways to do it, if a fellow is willing to part with a few bucks. The Lee Collet die works brass much less and does a far better job of neck sizing. Whether or not it would have to be expanded after that depends on the size of the bullet.

I also have a custom expanding plug for my 30 cal M die that tapers from .307 to .317 is .001 steps. I run it down into the case until I can just start the gas check.

I also use Vickerman seaters which removes any chance of bullet tiping and lead shaving.

[sundog]

btw, I had to use 8x57 seating die. The boolits are too fat to use the .303 seat die. Same thing happened to one of my '06 loads and I hand lapped a seating die so the boolit would reach the seating stem without interference.

If it don't work, modify it!

[Char-Gar]

Corky... Report back how that Fatter 30 is working for you. Sized .315 it does well in my 1945 Longbranch with a fine bore, but a worn throat . It should, as this was the rifle, I used when setting the final specs on the bullet. It has a bore diamter of .307 and who knows what the groove is. Every time I tried to slug it, the slug slipped out of those two shallow grooves and rides down on top of t he lands.

I have an old Lyman 303 PA (Precision Alignment) seating die that is big enough to take these bullets. A couple of years back a guy sold a butt load of these things on Ebay. He bought a large old stock of Lyman stuff that had been stored for years. I bought about half a dozen of these dies in various sizes and they run about .004 larget (inside) than most steating dies, making them just the berrys for cast bullet seating.

[Larry Gibson]

With all my .30/.31 cartridges I find the standard FL or NS die will size the neck down too much. The expander ball then expands it out and then the M die expands the case neck out farther. All that work hardens the brass too much and leads to premature split necks. Annealing can help but does not solve the problem. Also seating a .314 cast bullet in a neck sized to .306 inside diameter (the inside diameter after the .30 M die is used) can damage the bullet in seating or make for a very bad runout.

I solved the problem with a Redding bushing die for the 30-06. I shortened the die by taking enough off the bottom so that the .303, 7/65 Argie and 7.7 Jap cartridges may be used also. With several bushings .002" apart I can size the necks so the M Die, either .30 or .31, expand the necks just .001". Thus the necks are sized just enough for the proper neck tension on the bullet regardless of it's diameter. For bullets larger than .312 I size the neck to an inside diameter .002 smaller than the bullet diameter and use the Lee Univeral die or the .31 M die to just flair the case mouth. Necks are minimally worked this way, annealing need is rare and I've not lost a case to split necks in some time.

I also use this same '06 bushing die to NS 6/5, 55, 6.5-280, 7x57 and .280 Rem with the appropriate array of bushings. A case is put in the shell holder with the ram up and then the die w/o a bushing is screw down until the shoulder of the case bumps into the shoulder of the die. The die is backed off 1/4 turn and a steel flat is laid on the shell holder and raised against the bottom of the die. The die lock ring is then tightened down. This squares the die to the ram/press. The one '06 die and various bushings are a vary versatile tool that loads numerous cartridges.

Larry Gibson

[rvpilot76]

I turned a mandrel for my Lee Collet die for my Fatter 30 boolits and my Savage SMLE. I turned it to .315, as my boolits get sized .316. They seat with little effort and maintain their integrity (both boolit and brass-especially in the neck area), and then I crimp the whole affair with my Lee Factory Crimp Die to keep the boolits in place in the neck. Works good for me.

Kevin

[Buckshot]

.............newfoundlander, What kills good brass is overworking. Pretty obvious, eh? Most common dies make brass over after firing not so it will fit YOUR chamber again, but also Tom, Dick, and Harry's too. As we know, the part to die first (and it kind of kills off the rest) is the neck. The common die really sizes down the neck way more then usually needed, and then the expander ball opens it back up to some minimum ID the manufacturer feels will work for most everyone.

If your partner is really interested in making his brass live, he'll get a bushing die and chamfer the mouth of his casenecks. With casenecks sized to an ID of .002" under boolit ID and a champher he won't need the M die at all.

Consider the above. Brass at the mouth is .010" thick with a neck ID of .312" for his .314" boolit (we'll assume). With a chamfer that removes .004" of the .010 thick casewall at the mouth the boolit has a short funnel to start in and no belling is required at all.

Even set up like this if the case mouth is consistantly crimped I'd anneal the mouth maybe every 5-6th firing. More often if splits show up earlier. Some brass will stand more then others.

................Buckshot

[Shiloh]

I turned a mandrel for my Lee Collet die for my Fatter 30 boolits and my Savage SMLE. I turned it to .315, as my boolits get sized .316. They seat with little effort and maintain their integrity (both boolit and brass-especially in the neck area), and then I crimp the whole affair with my Lee Factory Crimp Die to keep the boolits in place in the neck. Works good for me.

Kevin

Lee Precision nicked me $10.00 to turn one of .308 diameter for my .30-06 collet die for using .312 cast boolits.
It took about 8 weeks and the lady who took the order thought I was completely daffy for even making the request.

Shiloh:castmine:

[sundog]

couldn't you take a rap of flue tape? beagle it? would the collet still work, maybe with a little lapping?

[Shiloh]

He already has a set of Lyman dies that came with the appropriate M Die so he's not really looking to replace it with something like a Lee Universal Expander unless it's warranted.

I've had fine performance from my Lee Universal Case Expander.

Shiloh :castmine: