What an Age of Sail breech-loader would require

What would it take to develop and deploy a reliable breech-loading naval gun during the Age of Sail?

Much better iron or early steel, a secure screw breech, and the industrial knowledge to manufacture both consistently; the same breakthrough would accelerate iron warships too.

A reliable breech-loader would require more highly refined iron, approaching steel quality, and a closure such as a screw mechanism that could withstand firing pressure. Loading from behind the gun would reduce the need to run it inboard and permit a longer barrel. The expected benefits include safer loading and greater range and accuracy. The counterfactual then assumes access to later metallurgical knowledge, funding, and suitable processes around 1790. Under those assumptions, the industrial advances extend beyond artillery toward an early Warrior-like iron warship. The 110-pounder is used as an example from the historical transition at the end of the Age of Sail.