Then you don't know what you're talking about.

I have a 7x57 and 8x57 case sitting right next to me, and yes the 7x57's neck is longer--by .066 inch.

You also might want to do some actual research on the history of the two rounds, instead of jumping to conclusions on the basis of your "eyeballing".....

“Montana seems to me to be what a small boy would think Texas is like from hearing Texans.”
John Steinbeck