I agree about 8mm brass perhaps if DWM or RWS brass is used. I find Norma brass, while it is loaded to higher factory pressures than the same case in the US (in 8mm), that it is a bit soft in the head area for my liking, showing greater expansion than the other two mentioned. This seems to occurr with almost all Normal brass. Indeed, back in the 70's, we used it for lighter 200 meter match loads only.
; I think because it's loaded to such low factory presures, that perhaps the WW and RP in 8mm Mauser might not be as heavily made in the web area. Sectioning a couple for comparrison would show whether it is as strong as .270 and '06 brass or if it is indeed, more lightly made.
; When making big changes in ctg. cases, I make my own tapered expanders. With them, I can use 7mm mag cases for .458 WW MAG. brass and one pass is all that's necessary - from 7mm to .458 in one step. I don't anneal, either, unless the first or second one splits. When annealing, I only anneal 1/2 the neck, leaving the shoudler/neck joint wiht enough strength to withstand the pressure. If the whole neck and shoulder is annealed, the neck will generally collapse into the shoudler.
: As to turning necks, no problem with a K&M hand tool, or Forester inside neck reasmers on the little lathe-type case turner. Everyone has one anyway?