Thanks for that info Rothhammer: much appreciated.

Looks like 54gr of smokeless behind the 160gr bullet gave 2700 fps in 1939, and my load sequence with AR2209 was headed right there!

I actually made up loads to 56gr but didn't end up shooting them.

A fifty-bag of nice shiny Norma 300WM unprimed brass is sitting on my reloading bench at this moment, waiting for the next iteration.

Hopefully tomorrow...