I have a set of early Dave Talley rings with bases. The rear base is .140” thicker than the front base. The rear screws are .450 c-c and the front screws .500c-c. Talley couldn’t tell me what they fit. Any ideas?

0.504 is common spacing.

0.450 couldn't find that spacing in Kinks book crossref.

total thickness would be better reference

This is Weaver numbers

Old Weaver "Tip-Off" mount hole spacing for Mausers and pre-64 Winchester M70's; based on an old thread from another forum (Texas Hunting). Obsolete hole spacing.

https://texashuntingforum.com/...base_drill_holes_0.4

I have several FN commercial actions. I’ll just have one drilled to mount these bases. The rings are 30mm.

Thanks fellows.