Are all the case "blanks" for a given family the same . For example arethe 308 , 7-8mm mauser, 06' drawn as the "basic" case before getting their heads and necks . What about straight wall cases 38,357,357 maxor 45,454,460 ?

I read some where that this is done for some of the straight and tapered40 and 45 Black powder cartriges ie 45-120 is like a basic case for the 45-110,90,70 etc .