[kronckew]

at the time of sinking, the mary rose was thirtyfive-odd years old, and the pride of henry 8th's fleet.

he'd just had it overhauled and upgraded to use the newer long barrelled cast iron cannon. (bronze was better but very expensive). the iron bores were much less forgiving than bronze bores, and iron projectiles with any imperfections could stick in the bore, catastrophically. lead covered iron projectiles would 'lubricate' the bore, preventing the sticking (and reducing wear and tear), and allowing less windage for better efficiency and range. tests conducted with contemporary cannon repros and iron shot were more than adequate to penetrate enemy hull planking of a thickness similar to the mary rose at 90 meters. the repros no doubt had better bores as they were machined with more modern machinery.

the new cannon were heavier. the decks were strengthened to hold the additional cannon, and the crew was increased to man them, and just on general purposes (from 200-ish to 400-ish).

sadly, the mary rose sailed on it's last fateful day, and apparently with a couple of hundred extra crew as well as the extra weight higher up, was quite unstable (no uscg or lloyds of london back then to approve stability plans) . the guns were cleared for action by the unpractised crew as they manoeuvred to attack the frogs, and as the vessel healed over, the lower still open gun ports were submerged, zillions of gallons of seawater entered the ship and it sank like a stone without firing a single lead covered iron shot. only about 35 survived out of the 400 or so on board. the rigged anti-boarding nets trapping many, the survivors mainly were from the top-men in the upper rigging. the lines of communication and command in the unpractised crew were strained, and there was likely not enough time or knowledge to ensure guns were run back in and the ports closed as the ship turned. the officers were political appointees, noblemen, and probably didn't know port from starboard let alone how to command such a ship.

i managed to tour the remains in portsmouth during one of the periods when they were not spraying it with glycol/water mix. eerie and claustrophobic. they had racks of longbows for the crew, that came from the wreck & looked like they could still be strung and used. they'd set up a repro you could try drawing, it was 120# pull or thereabouts. the museum is well worth a trip if you are in the area. hms warrior is also worth a visit nearby, as is hms victory.