Anyone can correct me if I'm wrong here...but I think Weaver got a little lazy back in the day of sidemount popularity. LR 98's are a hair over 1.4" dia, the most popular rifle of the cottage industry sporterizing was the 03 Springfield at 1.3" receiver dia. (also the small ring Mauser) and they just went with the 1.3" design, to reduce inventory and manufacturing, thinking nobody would mind if the scope was .050" off centerline. Just my opinion.
