I find anything over about 10 pounds to be tiring, but that's mainly because most rifles we hunt with are lighter than that. Were we to only hunt with heavier guns, we might 'rise' to the situation.

In 1850 India, 9 to 9 1/2 pounds was considered the correct weight for a Gentleman's double - 14 to 16 bore. with larger gauges, 12 to 10 being another pound. The larger yet bores, 10 and 8 were normally relegated to gun bearers.

I submit that 10's weighing 14 to 15 pounds must have been meant for African hunting. Too, different makers made them different weights as standard I suppose.