Arrows versus armor in fantasy fiction: can a bow and arrow really beat armor in the real world and in fantasy?
The bow and arrow has existed as a hunting tool and a weapon of war for thousands of years. Every major culture devised a means of launching a sharp stick over distance at high speed using a second, springy stick and a length of cord. Add a hardened steel tip to the arrow and you have a lethal weapon in the right hands.
But the target also matters. Almost any kind of protection alters the lethality of the arrow. But by how much?
Base Assumptions
In order to defeat armored targets you need kinetic energy, the closer the range, and the higher the draw-weight of the bow, the better. You also need extremely hard, tempered arrow heads of better quality than the armor itself. Finally, the archer needs sufficient muscle and skill to shoot the thing.
Real world shooting
Let’s baseline our assessment on real-world archery. No magic, no ‘lucky shot,’ just a skilled archer with a warbow and hardened steel arrowheads. We’ll imagine a fit adult male shooting 60 to 80 yards with a bow drawing around 100lbs. What’s the chance of penetrating the target to cause injury or death?
Padded cloth
Many medieval peasant soldiers wore a padded gambeson; canvas stuffed with wool. Resistant to some sword cuts and weak thrusts, the padded jacket might slow an arrow, but not stop it.
Hard Leather
Any kind of hardened leather will slow an arrow and reduce the penetration. The archer has half a chance of piercing the target.
Chain mail
The interlocking steel links in a chain mail hauberk pitches offers good resistance against steel arrowheads. The archer has an outside chance of splitting a ring and penetrating the mail with a narrow-point bodkin arrow head.
Plate armor
Steel plate not only offers the best level of protection, the shaping of the plate also serves to deflect missiles. Arrows skim off the curved surfaces, denying a direct hit. Any arrow hitting it head-on has to penetrate 3-6mm of steel. Ordinarily, the archer stands little to no chance. Ordinarily.
In extremis
A friend of mine used to demonstrate longbow archery and could, on occasion, pierce a thin 3mm plate with a direct hit from 2o-yards. The bodkin tip at high velocity and close range becomes an armor-piercing round with enough kinetic energy to heat the steel on impact and punch through. But you can’t rely on this. Not under battlefield conditions. And by the time the enemy is close enough, you’re in all kinds of trouble.
That doesn’t mean all plate armor is equal. Bronze is softer than steel. Cheap steel for a retained knight is softer than the bespoke harness crafted for a prince. Not every plate item has a consistent thickness; cost-saving and the skill of the smith come into play. But for the most part, steel armor is proof against most long range attacks.
The missile gap
But what, you say, about aiming for gaps in the armor, for soft tissue? While the bow is a precision weapon, it’s not a sniper rifle. Over long distance against a moving target, the chances of hitting gaps in plate armor are slim. Arrows lose penetrating power and accuracy over distance.
Sure, there’s an argument for aiming at legs, knees, elbows, shoulders. Maybe the face, if not covered. But marksmanship declines with the smaller target, as any soldier or police officer will tell you. That’s why they aim for the central mass of the body. With guns.
Fantasy land
But what about fantasy archers? Legolas? Gilgamesh? Hercules? Well, it’s fantasy. Anything goes. A magic bow can shot a mile. A magic arrow can shoot through stone. A demigod can draw a bow at 500lbs. The only limit is whatever law of possibility the story-teller decides to apply.
Maybe Archie the Archer has a magic bow and arrow drawing 250lbs and better than 20-20 vision, he can shoot anything. Until he encounters Hank the Tank in his magic plate armor that’s proof against artillery shells. Maybe Hank has (gasp) Plot Armor. Nothing gets through that. Unless Archie has to win the epic climax, in which case, Hank, it’s game over, man.
Setting the rules
Each story sets its own ‘rules’ for what’s practical. Does it follow real world physics and materials? In which case lightly armored warriors risk death and injury while plate-armored knights laugh in the face of the enemy with sticks and string. Or does it lean into myth and magic? In the epic, anything goes.