Sorry, I'm watching with interest. Need to slug the barrels on a couple rifle and get a mold too.

Pentz - are you going to shoot the bullets with smokeless or black powder. And remember, Accurate will cut the mold smaller if you probably will need it
All my Accurate mold are aluminum except one brass one and they cast with no issues

These bullets will be 20 or 25-1 atop smokeless.  The aluminum mold sounds good.  I have NOE aluminum molds too.

By bore diameter I presume you mean grooves at .308 - a bore-riding bullet at .309, then.  My case necks measure .326 with very slight tension on the inside calipers.  So the stop ring should be .336?  I understand the concept of using the case mouth to jam the nose and stop ring into the bore and throat.  The rings below the stop ring would then be sized to .326.  That should get it.

I had difficulty with the concept of a groove-diameter nose - Fine with a breech seater but worrisome with a case that has to be thumb-seated.   

The tilting block of my Aydt drops sufficiently to leave a small edge at the rear of the block mortice.  I bet one could engineer a breech seater to lock onto that edge....

If the inside diameter of your fired case necks measures .326 then your chamber sounds to be oversize. I would think they shouldn't be over a few thousandths greater than the groove diameter. My 8.15s with .316 grooves have fired case necks that measure about .325 outside diameter. Is it possible someone in the past history of the rifle has run a 32 Winchester Special reamer in there? I seem to remember that was an expedient after WWII as Gis returned with rifles and no ammo.

I wondered about that too.  While I do not have 32 cases on hand, a 30-30 case will not begin to seat, stopping .650 short of chambering.  Don't know what to think of the larger neck size.


oneatatime wrote on Feb 2^nd, 2016 at 1:03am:

Was wondering because .325 seems a little big like Pentz .326. Just measured the mouth of a fired case from my Aydt made in 1927. Measures .321-.322.  Seems to me my older Stahl made in 1891 which has the early chamber, has a larger neck diameter. 
Maybe this is why they offered hollow base bullets in the old catalogs?

         Joe.

This is my case that I use for BSing, it's 1.96 long and the bullet that I BS. The base band is .315 and the nose is .307. It's a oversize 308329 that I reamed the GC area to .315. 

With the bullet seated, the neck measures .333. I just started the base in the case, straight and then pushed it in the chamber and closed the breech block. The COAL is 3.021 and there is .130 of the base band, in the case mouth.

The nose @ .307, engraves the lands for .160 and the bullet is 1.192 long.

You can't see it but, the last .100 of the case mouth starts a taper from .340 down to the .333 and that would be the start of the "throat", if you can call it that.

This is what I mean by "adjusting" the length of the case to fit your bullet and throat. The way my chamber is, I could have a .325 SR at the end of my case and since, the exposed band measures .3125 and doesn't engrave, I could replace it with at least a .313 band.

BTW, I shoot this bullet BSed w/o any tipping.

Frank