I had a .62 caliber, iron-mounted, Lancasterish flintlock longrifle.
The concept for which started out as a fullstock Hawken rifle. Of course, no such thing as a fullstock flintlock Hawken rifle has ever turned up.
So that .62 caliber flint longrifle was just a fantasy rifle. But, it shot extremely well.
Weighing in at approximately 8.5 pounds, recoil with a 0.615" diameter × 348 grain pure lead ball over a 75 grain charge of fffg black powder was very tolerable. I never considered recoil in the shooting equation for the short amount of time that I owned that rifle. I regret not having had the time to ever hunt with that rifle.
I am considering going back down the flintlock longrifle road, and the choice between a .58 caliber (Colerain gain twist), a .62 caliber (Colerain gain twist), or a Rice .66 caliber (0.672" bore diameter)(1:48" twist) is a hard one to make.
Been leaning towards a .62 caliber, Early American pattern barrel from Colerain, which measures 38" long. The gain twist in the 38" long barrel starts out as approximately 1 turn in 76.5" at the breech, quickening to 1 turn in 36" at the muzzle.
If Scott would make the 38" long barrel with a breech diameter of 1.100" across the flats octagon, the waist to measure 0.810" A.t.F. octagon, and the muzzle to measure 0.995" A.t.F. octagon, then the barrel should make up into a longrifle weighing in at approximately 8 pounds. Maybe even have it made as an octagon-round barrel to shave a little more weight off of the barrel.
Been thinking about a contemporary, halfstock, flintlock, English Sporting Rifle using such a barrel.