Quote Originally Posted by Alan de Enfield View Post
My understanding was the dimensional consistency. I have not been able to identify if this was bullet dimensions, or case dimensions. I am guessing that as it resulted in jamming / blockages / non-ejection that it was inconsisten case dimensions.


Just as another example ( later manufacture and now made to SAAMI dimensions) the difference between US manufactured (commercial) 303 and 'mil-spec' 303 dimensions.

The Win cases are the 'thin ones' and the Prvi-Partisan are the 'thicker ones'. Using the Win. cases with the thin rims, can result in you increasing your effective headspace by ~ 5 thou. The Win. and Rem. tend to be at the bottom end of the specification (Min spec 0.054") whilst the PP and Mil-Spec tend to be around the top-end (Max spec 0.064")

Notice also how thin the 'SAAMI' cases are around the "web"
Thank you Alan!