Hi,
I actually own a replica roman Pilum built as those you see in the game of the 1st Century BC type.
I find the Pilum to be a well balanced and very easy item to throw.
Its initial design based on using it I think was to disarm sheilds, the tip would stick into the shield and the bulky part would weigh the sheild down making it difficult for the opponent to hold thus allowing the Roman to get in with his sword and shield.
Obviously he may have scored lucky and got someone with it but initially I believe the Pilum was for disarming rather than piercing.
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