Note the Luftwaffe drilling was chambered for the 9.3x74R as Dave said, not one of the 9mm rounds. The M54 was probably in the 9x57 chambering. A 9.3x74R is ballistically pushing very hard on the .375H&H & could not be re-chambered to a .35 Whelen as both its case & bore are already larger than the Whelen.


Miller/TN
I Didn't Say Everything I Said, Yogi Berra