Worm holes.
Typical on horn butt plates

This is the Trigger guard, any way to reasonably remove these initials, and maybe replace them with my Grandson's?

If not, I guess I will tell him that RLM stands for Really Love Mom. :rotf:

Bill, Love that early Midas! I am shooting a first year 20 gauge grade one now. Built in 1949,the first year for 20 gauges. These early superposed were so much better built than the later guns. The early guns are lighter and better balanced. My 28" 20 weighs just 6-3 and has the slim grip and forend typical of the pre 1955 guns.

John, what is the serial number of your first year 20? Mine is #605. No information on my gun from Browning. I would try to get info from FN is I knew how. My #605 is mint and may be unfired. It is 28", solid rib, modified and full. I bought it off the rack at Albright's in Easton.