I once read something about a group of men that were at a gathering in the 1750's. One man was bragging about how good his rifle shot. He had been shooting at this gathering and not doing all that great, and someone remarked that it didn't appear that his rifle was all that great. The fellow with the rifle proposed a wager with the fellow that made the remark, he offered the commentator the first shot. A mark was placed and the first fellow shot, coming close to the mark. When it was time for the fellow with the rifle in question to shoot, he said "OK, Don, time for you to shoot". A young man stepped up and settled down on the rifle. The other shooter protested "what is this" he exclaimed. "You can't have another man shoot for you". The owner of the rifle retorted "The wager is who has the better rifle, not who is the better shot. Shoot the mark, Don". The young man took the shot, dead center of the mark. As the young man handed the rifle back to its' owner the loser in the competition said "that was good shooting Don". The young man replied "The name is Dan'l, Dan'l Boone".
While most ML rifles should be cable of 1.5" groups at 50 yards, not all shooters are. Especially if it's a flinter. A 3" group is good enough as long as the shooter limits his shots.