Foresee a problem?

[Lead melter]

OK gang, got me an idea (this might be scary).

I have 3 M-N's and each has a preference for a different cast boolit size...they vary from .313" to .316". Thus far I have been using the Lee C312-185-1R mold beagled to cast at .316" and then sizing accordingly. The boolit shoots well enough, but best accuracy in any of the rifles is when the driving bands of the boolit is positioned to be just slightly off the rifling. Anyone familiar with this boolit knows it has a nose about half the boolit length and seating the slug out far enough to come close to the rifling allows case neck purchase of only a small amount of boolit shank. Not the best situation for accuracy.

My idea is to use the Lyman 319247 mold made for the old 32-40 round. It's flat nosed, plain based, and the short nose/long shank design should place the slug bearing surface far enough into the throat to get good accuracy, yet allow good case neck grip on the boolit shank.

Well, at least that is my thinking.

I know I can size the boolit down from the stated .322" to .316", then to .313", but the question arises, has anyone played with this mold or similar for such an application? Don't want to throw away hard earned $ on a far fetched idea.

Watcha think?

[runfiverun]

why not just use the larger mold for the larger rifles and the mold you have now for the tighter bbls then your sizing would be minimized for each one.

[Larry Gibson]

Lead melter

Not a bad idea at all. I regularly size 323471 and 323470s down to .315 for use in some MNs (also for PP back to .325). I have also supplied some bullets for sizing down to .316 and .318". The sizing down is done in one pass through a Lee sizer (the .316 and .318 are in honed out .314s). To keep the bands and grooves in good shape during sizing seat a GC and lube (fill all grooves including the crimp groove) before sizing. The .315 (actually .3155+) are sized through a regular .314 Lee sizer. Springback of the harder alloy I use makes for the slightly larger bullet. These cast bullets sized down accordingly shoot as accurately as any cast are going to in MNs.

Another problem with many MNs is the chamber leade many times goes from the outside of the chamber case mouth to the rifling instead of the inside of the chamber case mouth like we are used to. This makes for a larger diameter leade at the case mouth. A softer alloyed bullet driven relatively hard can swage out into this larger leade and then is swaged back down as it enters the bore. This most often happens to the base of the bullet. This swaging back down creates imbalances and can create a non-square base. Both adversely affect accuracy.

Using MNs with such leades/throats I use a harder alloy or WQ and use as large a diameter bullet as possible. I ignore the bore/groove diameter as that iwll take care of itself. I prefer to use a cast bullet with a sized or unsized diameter that has just .001" clearence of the inside diameter of a very well fireformed case mouth, a tight "slip fit" if you will. I then neck size for .002" neck tension using a Redding bushing die (topic covered in another thread). Accuracy with many oversize MNs can be truely amazing with such cast bullets, especially the 323470 and 323471 Lovern style cast bullets sized appropriately.

Larry Gibson

[nicholst55]

Larry, what Redding bushing die are you using to neck size your 7.62X54R brass?

I really wish that Lee would begin offering a collect die in this caliber, and Redding a bushing die! It would sure make life simpler! I wrote to Lee some time ago asking for a collet die. Their response was to send me a catalog.

[runfiverun]

redding will make custom bushings if you want.
and forget asking lee for anything that works.............. you at least got their polite reply

[Larry Gibson]

nicholst55

here's my post from the other thread. Note; you only have to get the Redding bushing die, not the whole set, if you already have a regular set of dies.

7.62x54R NS’ing

Get a Redding bushing die for the .284 Winchester. Shorten the bottom end of the die enough that the shoulder of a fire formed 7.62x54R case in the shell holder will just be short of bumping into the shoulder of the die. If you have fired 7.62x54R cases segregated for more than one rifle use the case with longest head to shoulder measurement. That way the shorter cases will fit without readjusting the die. The die can be shortened with a bench grinder but is best done with a lathe. A machinist or gunsmith should not charge too much for this if you can’t do it yourself. Then with 3-4 bushings .002-.003” apart you can perfectly size the size the case neck with .002-.003” neck tension for bullets of .308, .310, .311, 312, .314 or .316”. This gives a perfect fit for the bullet diameter used. The Le case mouth flaring die perfectly compliments this. I’ve not lost a case to split neck or incipient head separation since I began using this method 20 years ago and I shoot several 7.62x54Rs quite a bit.

I still have a box of original Norma cases (factory ammo) I bought in ’68 for my Type 53 and M91/28 I brought home from Viet Nam. It had been fired in the Type 53, full length sized 3-5 times and then neck sized I don’t know how many times with no loss of cases. Conversely I picked up some once fired Norma cases and FL sized them several times for use in the M91/28. The cases were sized quite a bit to get them to chamber. After several firings I started to get incipient head separations. Twenty years ago there wasn’t any NS dies for the 7.62x54R so I made my own as above. Most all commercial NS dies squeeze the necks down so .308 bullets can be used and then depend on expanders to expand them. The nice thing about the Redding Bushing die is you size the necks to only what is needed for the diameter of bullet used. This minimally works the case necks. I’ve also never needed to anneal any necks when they are minimally sized as such. I have 2 fifty round boxes of Norma cases that have been fired over 20 times in my M39 with not a single loss.

Yes the Redding Bushing die + 4-5 bushings is more $ up front but in the long run I have not only saved with no more case loss but I get very accurate reloads with cast and jacketed bullets. My M91/28 sniper shoots moa with both.

Larry Gibson

I'll add that the same Bushing Die and bushings can be used to NS the 7.65 Swiss case, if anyone has one of those.

[dmdracer]

In my "research" about mn's (see other thread), I just last night discovered this thread :

http://castboolits.gunloads.com/showthread.php?t=22578&highlight=762x54r

which is basically the same as Larry wrote above with a little more info on what he said here.

hope this helps some

Dave.