Runar, it works!
Im building a little .29 caliber rifle and wanted a 9/32 ramrod instead of just going with a 1/4 like most do. Bought a length of 9/32 O-1 drill rod and after a few days of bouncing around ideas, decided to go with your design and ground a tip on the rod.
Was slow going, maybe a 1/4 at a time to clear chips, but got it done. Drilled straight, side to side came out perfect, wandered down a bit, about a 1/32 at the breech, probably caused by ramrod channel not being perfect, but Im very happy with how it came out.
Whittled down a 5/16 Hickory ramrod to 9/32 and its good to go.
Bob