Harry Pope always said a Man's rifle (for Scheutzen shooting) should be 16 pounds and a Woman's rifle should be 12 pounds.
Of course, some discretion/leeway could be allowed for stature, strength, etc.

What I find quite interesting is that many men today, in a shooting game that requires ALL offhand shooting, struggle with or say anything 8 pounds or over is too heavy.

I am referring to ML Rifle Rendezvous trail walk, round ball rifle or smootbore shooting - where we up in the North prefer longer, 42" (or better) barreled rifles of 10 to 12 pounds for a superior hold on target. With a flintlock rifle, ie; slow lock time, the heavier the better.