in Samuel Baker's book Wild Beasts and Their Ways in one paragraph in Chapter One he states "I have shot with every size rifle from a half pounder explosive shell, and I do not think any larger bore is actually necessary than a No. 8, with a charge of twelve to fourteen drams of powder. Such a rifle should way 15 lbs., and the projectile would weigh 3 ounces of hardened metal." Get a copy of this book if you can, it's a fascinating look into large bore game hunting in the BP era.