Thanks again for the lively discussion on this somewhat obscure topic. I don't own a .30/06 so I guess I'll never shoot any .32 ACP from a rifle with an adaptor, but it sounds like fun.

I'll have to disagree with JW on the correct crimp for the .32 ACP. Both the .25 ACP and .32 ACP headspace on the rim, not the mouth, of the cartridge. The .380 ACP, 9 mm, .40 S&W, 10 mm, and .45 ACP headspace on the mouth. My source for this is the SAAMI website, which has complete technical info on all current cartridges including chamber drawings that show the critical headspace dimension.

My reloads with .312 bullets in American (thin) brass had no problems with a roll crimp (which is what my Lee dies do - they don't offer a taper crimp die in this caliber). I think I ran into trouble with the European brass because I seated and crimped in one step and created a slight bulge that was too much for my chambers to accomodate with the thicker brass. However, with cartridges that headspace on the rim, either type of crimp can be used. Interestingly, Fiocchi cartridges have bullets with a cannelure to accomodate a roll crimp, like revolver cartridges.

The Speer, Hornady and Lyman manuals don't mention what type of crimp to use for .32 ACP. Lee dies roll crimp and RCBS dies taper crimp in this caliber, and Hornady doesn't specify which their dies do. I guess you "pays your money and takes your choice".