I think I already knew about this, but appreciated the reminder. Though I don't need it just now.

I'm currently trying to sell a novel set in an alternate universe where they've had overt magic use for more than a thousand years. Technology has advanced, but in different ways than here. (They're only just getting automatic gunpowder weapons and internal combustion engines.) They have had practical firearms for a while, and arrows are pretty much obsolete. However, that info could come in useful.

Here's a similar bit of Medieval arrow trivia. While layered silk armor would not stop a hard-shot arrow, it was so elastic that the arrow would push it into the wound. Just tug on the silk cloth (I don't think this works with just one or two layers, like you'd have in a garment) and pull the arrow out. :-)

This would also work with very low-powered firearm bullets. A frontier doctor reported pulling bullets this way out of two recently deceased gamblers who had been caught cheating. It just happened they were wearing folded silk handkerchiefs in their shirt or vest pockets.

Silk is actually stronger than kevlar (speaking very generally about two variable materials) but is *too* elastic to make good ballistic armor.