Mil-Std-1913 was revised, and page 4 was replaced on 10Jun99, replacing the page from 03Feb95. This was revision A.
Base document (Rev NC) - astimage.daps.dla.mil/docimages/0001/93/41/1913.PD5
Revision A - astimage.daps.dla.mil/docimages/0001/80/24/1913.PD8
Revision NC specified the rail width as 0.835 -.005. This means the allowable range is 0.830 to 0.835. THE WIDTH HAS NOT BEEN CHANGED.
The only change I see on the drawing is the addition of 0.060 radius where the rail meets the flattop.
I did measure my LEGP (#27) to be 0.835 wide, and my Bushmaster to be 0.832. Both w/in spec
Well, I just got some $$ Leupold Mark IV rings and they wouldn't fit the Bushmaster. Too loose, rattled around even when bottomed out. I called Leupold and they sent new keepers.
Maybe it's a difference between Weaver and Picatinny that is causing the troubles.