Goodness...they are sort of dancing around both cartridges. Don't take my word as gospel and wait for others more familiar with both cartridges than me but I think it is the 9.3 X 74R. Case length and shoulder dia. seem to indicate that and the thickness of the chamber at the rear of the barrel seems to me to be fairly heavy for the 9.3 X 72R Sauer and more in line with what the X74R cartridge would be. The length of the neck seems to favor the X74R also. How do the neck length dimensions compare? All the info you provided was great. Thank you for taking the time.

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