Interesting guns - BUT.

If the range in the link is the only one used for these 'interesting' guns, I question why?

22.8 meters on the slope (18.1 meters horizontal range = 19.73yards) is just under 25 yards - 24.85 yards which in my opinion is a meaningless range for the use rifles - except for perhaps low powered air guns.

Even my smooth 20 bore flintlock will put 5 patched balls into a 1" or less group, rested, of course, at that range and it has but 1 sight, the blade near the muzzle & no rear sight.

LOL - well, 4 out of 5, at any rate at 25.68 meters = 28 yards.