you've made it to the final round

of this competition.

Now we're sending you back to your home forges to recreate

an iconic weapon from history.

[dramatic music]

It's a rock-throwing crossbow, gentlemen.

[upbeat rock music]

- Today, I'll be pretesting the rock-throwing crossbow.

♪ ♪

This is a little bit different for me

because I'm an edge weapon guy,

edge impact and stuff like that,

so I don't like projectiles that much

'cause I want to feel up close and personal.

But it's still a weapon that I can shoot.

- Nick, line up on Doug here for the firing.

- Now, this is actually a new weapon for us.

We've never done it before.

- And Jacob, you're set with everything else?

- Uh, yeah.

- Using Dave's crossbow for this test,

it really is about how the functionality

of the weapon works,

'cause everybody's gonna build it differently.

The weight, the way you're gonna pull it,

everything's gonna be different.

At least I have a basic understanding

of the mechanics of how it's supposed to work.

- I'd say you're probably just a hair high still.

Right about there's perfect.

- Gotcha.

We're doing a test on a ballistics heart.

[dramatic music]

It's a KEAL test,

but by keeping it away from a torso,

without the ribs or all those,

we can actually see how deep the stone penetrates.

♪ ♪

One of the things about projectile weapons

in this competition

is we don't have a chance to sight it.

We get three shots.

The first shot is usually how I'm able

to gauge and make my corrections.

- You're low.

You're about 2 inches down.

- Now I can, for a second and third shot,

auto-adjust where I need to go.

♪ ♪

Got it.

So, the things that we're experiencing

with the pretest, we say, okay,

by using it, I know what to expect.

I could do all the research in the world

about this weapon, but until you pick it up

and feel it and test it--

you get a real feeling for what it can do.

Let's do this.

♪ ♪

- All right, weapon's hot.

♪ ♪

- And now we can cut.