According to Ripley's book, a stand of 11 inch grape, weighing in at 125lbs, would consist of 15 iron shot with a mean diameter of 3.55 inches each. I've read "somewhere" that the shot used were standard 6pdr solid shot.

I've see no reference to a 14 inch tube so perhaps someone else can address it but while Ripley doesn't gives specs on 15 inch grape it is noted that 15 inch canister weighed 207lbs with 600 balls of 1.3inch dia.

Hope this helps

Benny Austin