Quote Originally Posted by bovi
Since the pilum was designed to bend on impact, I'd guess it wasn't very good in prolonged fighting, but it would scare a horse I'm sure. Hitting a shield would probably render it nearly useless?
The pila wasn't actually designed to bend on impact, Hispanic and Britainnic ones don't. With that said it's not great as a thrusting weapon, the principle is the same as the later infantry square of the Napolionic wars. Horses don't charge a walls of steal for the same reason men don't. As a thrusting weapon though the narrow iron shank would probably vibrate on impact, going through anything other than flesh in hand-hand combat would be difficult at best.