How Accurate Are "Vintage Rifles" Video Left Me Disappointed

I was watching a video the other day entitled "How Accurate is this Vintage Rifle?" from Thompson/Center Arms using a percussion cap muzzle loader to which they had attached a scope mount and telescopic sight. Civil War snipers using similar rifles were able to hit targets hundreds of yards away with some recorded hits at 1,000 yards or longer. So I was disappointed when the guy shooting the rifle in the video was excited that he was able to hit a silhouette target at 300 yards.