Unspellable,
You stated:
"I pulled the firing pins and tried an unfired 7.63 Mauser round. Same results. None of them came close to chambering. Next I pulled out the cartridge drawings and it?s obvious the Mauser round will not chamber in a 9 mm."
"The 9 mm Parabellum is 0.380 in diameter at the case mouth. The mauser case is 0.397 in diameter at this point and to a distance of 0.007 in front of it. (At least going by the drawings in the Lyman pistol reloading book.)"
What brand of 30 Mauser brass are you trying to chamber in your 9mm's? I am using new brass from Old Western Scrounger with a 93 gr bullet handloaded to 1.36" oa length with no resizing of the brass. I tried these cartridges in a 1915 DWM, a 1918 DWM, a 42 byf, a 1936 S/42, and a 1923 Commercial. They chambered fine with no problem in all of these 9mm guns. The shoulder diameter on these cases is .370" and they measure .760" from base to shoulder.
It seems that even the "experts" can't agree on the dimensions of the 30 Mauser!. I got the following dimensions from my books: HANDBOOK OF CARTRIDGE CONVERSIONS BY John Connelly; 7.63 Mauser shoulder diameter=.370", length to shoulder=.735". 9mm Luger neck dia=.380, case length=.754'. DESIGNING & FORMING CUSTOM CARTRIDGES by Ken Howell; 7.63 Mauser shoulder diameter=.372", length to shoulder=.760" 9mm Luger neck diameter=.380", case length=.754". CARTRIDGES OF THE WORLD, 7th ed; 7.63 Mauser shoulder diameter=.370", 9mm Luger neck diameter=.380". <img src="graemlins/soapbox.gif" border="0" alt="[soapbox]" />