Re kcordell's post above, if I'm remembering correctly the chamber in that drilling was necked and had the typical (.43) Mauser base and rim dimensions of 13mm/15mm respectively.
We haven't gotten word from Silver on his prospective drilling as to whether the chamber is necked or what the base dimensions are, but most of this thread has been leaning toward the other and probably more common 11,15x65R "LK" that has a straight case with base and rim of 11,9mm/13mm respectively.
Dang Germans - too many similar cartridges!
