Agincourt was won because of difficult terrain, horses got stuck in, the arrows weren't the problem, but in the chaos the English archers killed off the knights with their cludgels. Also the Armour wasn't as fluted as a late 15th century armour is. It's the fluting or correct bending of Armour that makes the arrow not pierce through. So it should penetrate lamellar or brigandines without any problem for it is not as effective against arrows as a fluted Armour like a Gothic one.