I own a rifled black powder musket (Replica Springfield 1855). I can reload it, depending on conditions, in 30-40 seconds - not minutes. I would not advise standing 5 meters away and expect to have the ball not penetrate cloth. I can hit a man-sized target on a good day out to 500 yards. The Napoleonic wars were a mixture of modern weapons (Muskets and field pieces) mixed with the tactic of rigid troop formations that were a leftover from the days of fighting strictly with edged weapons. Field commanders on both sides quickly realized that the only way to avoid being cut to pieces at range was to fire the muskets and then charge with fixed bayonets. That tactic, along with aggressive skirmishing, became the norm for a long time. Depending on the distance between troop formations, everyone got off one volley and then it was the bayonet charge and hand-to-hand combat. For a look at the other side of musket fighting, Google the Battle of Four Lakes.