Maximum Amount of Bullet Sizing in One Die?

I know that some have reduced bullet diameter in stages (i.e. using different die sizes) to get to a final bullet diameter. What's considered a reasonable amount of reduction in bullet diameter that can be done in one die? Any difference if bullet is soft or hard?

Right now I air-cool my 311291s, PP, size to 0.309", load and all is well in a .308 Win. However, my WQ .375s were close to BHN 20 (LBT) and stripped- off the PP during sizing. Next time I cast, I'll simply air-cool and see what happens during the sizing operation. If that doesn't work, then I'll see if I can size a WQ CB to 0.001"/0.0015" above BORE, PP, and size to 0.001"/0.002" above GROOVE diameter. Comments anyone?

From what I know so far; regular lubed CB are typically sized to GROOVE diameter or slightly more. However the CB, used for PP, can either be first sized to BORE diameter and then PP OR PP and sized to GROOVE diameter (i.e. either way results in the CB being close to BORE diameter). Being able to just size a PPCB to GROOVE diameter is a lot faster and eliminates the need to buy more sizing dies. What approach gives better high velocity accuracy?

Best regards,

CJR

I size .310 down to .3105 and patch them back up. I have taken the 311284 over 3000fps in a 300 RUM with MOA accuracy. I take .459 down to .451 and they shoot fine patched backed up.

Pdawg,

Thanks for that info. I appreciate it! Looks like I'll pick up a couple more sizing dies. I assume you meant to say "0.310 to 0.3015"?

Best regards,

CJR

There Pdawg and I are at odds.
I size to .308, wrap, then size down.
My .30cals I size to .308, wrap twice, then size to .309. My .303 I size to .308 wrap twice, then size to .314.
I get the same results as Pdawg.

I have had problems with the patch getting loose when sizing down that much after patching. I prefer to have my bullet the correct size for the bore before patching. After patching I want to size just enough to remove excess lube and smooth the patch up.

Pdawg,

Your comment on the PP loosening after sizing an as-cast CB was interesting to me. Recently I sized some PP as-cast CB and found loose PP. I just assumed it was the Teflon/wax spray I was using and switched to JPW. It makes more sense to me now that sizing a PP as-cast CB from roughly 0.316"/0.317" to 0.309" would loosen the PP. Once the PP dries and shrinks it can't shrink again. Sizing initially, PP, and sizing again may be the key to consistent performance with PPCB. I'm looking forward to my next range session this week.

Best regards,

CJR

The patch MUST be tight on the bullet our you will get patterns, not groups.