Wednesday, 5 August 2015

Linothorax vs modern projectiles

Earlier this year I made a linothorax of the kind used by Alexander the Great's army.  That was a lot of fun, but making armour is only half the story.  The important question is: what sort of protection does it provide?  When Aldrete and co made their linothorakes, they tested them against the kind of arrows that were used in ancient Greece and found that the linothorax was very effective at stopping these arrows.  I don't have access to reproduction ancient Greek arrows, but in my family we like target shooting and we have several modern projectile weapons available.  This weekend dad and I tested the linothorax armour against an airgun, a slug gun, and a crossbow.  We learned that the person in most danger during this process is actually the shooter.

Now, just to recap, my linothorax armour is made the same way it was made in ancient Greece, using layers of linen fabric laminated together with rabbit skin glue.  This test patch is about 10 millimeters thick.  The thickness isn't exactly even across the whole surface, but close enough.  The linothorax functioned a lot like a Kevlar vest, by dispersing the energy of an impact.  Armour like this is good at protecting against blunt force trauma, and it will also give protection against edged weapons.

Here you can see what happened when we shot the armour test patch with an airgun: not much.

These shots were fired from 18 meters (top right corner) and 5 meters.  Interestingly, there was no difference in the degree of penetration.  There wasn't any.  The BBs bounced, leaving only tiny dents in the surface of the armour.  This gun will quite happily embed BBs in plasterboard or weatherboards, but linothorax armour absorbs and deflects the energy of the shots.

The airgun, plus the little dents it made.

Next up is a spring loaded slug gun with a rifled barrel, which belonged to my grandfather.  We tried both flat-head slugs and pointed slugs, and they all bounced.

The impacts from the flat-head slugs are ringed in yellow, and the pointed slug impacts in red.  Other than creating different shaped dents, there was no difference between them.

Next up is a pistol crossbow with a 50 pound draw, which is more like the kind of weapons the armour would actually have been used against.  Like the BBs and the slugs, most of the crossbow bolts bounced off the test patch without penetrating.

This photo shows you exactly how far the crossbow bolts bounced.  Circled in yellow is the crossbow, showing where it was fired from, 3 meters away from the target on this occasion.

A couple of bolts did stick in the test patch.  They went through all the linen layers, but only just.  The tips stuck out the back only a millimeter or so.  If you were wearing the armour you'd get a small scratch at worst and probably not even that, since the Greeks wore clothing under this armour.

For comparison, here's what happened when we fired the crossbow at a plastic shotgun target.

We learned that plastic does not provide effective protection against crossbow bolts.

Linothorax armour, however, does provide effective protection against crossbow bolts.

If you look carefully, you'll see that part of the bolt's steel tip is still visible above the surface of the test patch.  It has only stuck in the material and has not gone through.

We didn't test the armour against a shotgun this time.  For that we'll need to go to the shooting range and put some decent safety precautions in place.  Based on these tests, there is likely to be a significant rebound problem.  Whether the shot will be able to penetrate the test patch is a bit more difficult to predict, but will depend on the load.  It won't stop buckshot, but then very few things do.  Bird shot, however, will be interesting.  I expect the test patch to offer at least some degree of protection against bird shot.