How would six frigates with cartridge-firing breech-loaders have changed the War of 1812?
Short answerThey would fire faster, but period cartridges and metallurgy could also cause more dangerous failures and explosions in their own guns.
NotesThe counterfactual gives the frigates a clear rate-of-fire advantage over ordinary muzzle-loading opponents. The answer immediately qualifies that gain through the quality of cartridges and metalwork available in the period. Weak sealing, inconsistent ammunition, or inadequate metallurgy could produce additional failures and gun explosions aboard the firing ships. The exchange shows why a weapon's nominal firing cycle cannot be separated from the industrial reliability needed to sustain it safely.