Medieval Lord Threatened by Tyrannosaurus!

I’d send a company of pikemen and crossbowmen. The pikemen will be in front, preventing the dinosaur from attacking (like a horse, a T-Rex would be too smart to run into a hedge to sharp points), with the crossbowmen behind peppering it until they hit a vital organ or it died of blood loss. If it tried to circle around, I’d have them form a hollow square.

In other words, I’d use the same weapons and tactics the people of the time used against armored knights.

T. rex legs are not comparable to trees and you don’t cut right through it, just enough to make it useless, i.e. chopping into the Achilles tendon.

They could probably get some tips from these guys:

A ballista had a maximum range of 500 yards and was said to be capable of picking off individual soldiers at shorter ranges, so that would be my weapon of choice.

A T. Rex bone surrouded by many inches of muscle and tendon would, I believe, be nearly as difficult to hack through as a small tree, especially on a single terrifying pass with one one swing at best. You’re right though, cutting through enough connecting tissue would cripple it fatally. But, I doubt, it would disable it quickly enough that the knight would getaway without a whole lot of luck. I’ve been operating under the assumption that the knight should survive, as in the OP’s example of the hero vanquishing a dragon.

I’d be very curious to see one hit a moving target.

They were often used in combat against boats, so I don’t think it would be that difficult to hit a target the size of a house.

While that’s probably true if humans are around to finish him or her off, it’s worth noting that current thinking is that dinosaur bones healed unusually fast (something they passed on to birds). So in nature (i.e., without a bunch of armed humans trying to whack them) predatory dinosaurs probably did not always find a broken bone a death sentence.

A t-rex weighs as much as a mastodon. I have no doubt that a lance is a dangerous weapon to a mastodon. The knight can always let the lance get ripped out of his grip if he’s worried about getting unseated.

The t-rex might be more agile, but it’s still made out of meat. I say brave Sir George has a reasonable chance to cause some serious damage with a lancing.

But I’d say the best bet is to fight it with men surrounding it with spears.

http://www.youtube.com/watch?v=fkN6C1ur1t8 <–video with very graphic blood and hunting animal deaths

In this video near 2:20 a large group of African hunters take down an elephant without gunpowder or (apparently) anyone getting hurt. The video is very graphic but when I see it I’m filled with this crazy sense of pride. This is why humans rule the world. We’re weak and soft, but we hurl iron. I don’t think the t-rex stands a chance if the lord can levy 20 men with spear training.

Physics disagrees with you. The bullet has to “push” away from the gun. The amount of force it has going forward is equal to the amount of force it “pushes” against you and the gun. The reason it doesn’t hurt you to fire a gun is because all the recoil force isn’t concentrated into a point, like it is in the bullet.

The lance almost certainly has more kinetic energy behind the point of the spear than your hunting rifle did.

I like the ballista idea. I’d throw out some bait, zero in the ballista and just wait.

What worries me about getting close enough to lance or spear a T Rex is that I’m guessing they used their tail as a defensive weapon. I don’t see why they wouldn’t turn around and whip you with it in either scenario.

"Shhh! Be vewy vewy quiet. We’ah hunting T. wexes.

Hehehehehhehe!"

E. O. Wilson has said ants rule the world.

A guy in a small boat with just a lance could kill a huge whale. Some men died, but most did not.

According to wikipedia, the largest mammoths weighed twelve tons, while the largest T-rexs topped out at seven tons. Stone age cultures managed to take down the former on a semi-regular basis, so I imagine with some practice and painful trial and error, the more tech advanced medieval knight could figure out how to deal with the latter.

Recoil is a matter of momentum. Damage to the target is a matter of energy. The two are not the same thing, and it is perfectly possible for one weapon to deliver a greater energy with less recoil than another. I’m 100% certain that the lance would deliver significantly more momentum than any handheld firearm, but I’m not sure about the energy offhand.

Back to the OP, a very lucky human could hit a vulnerable spot and kill the dino (and it’d have to be luck, not skill, because a rex’s vulnerable spots wouldn’t be in the same places the knight would expect), but my money’s still on the pit trap or poison.

The tendons at the back of the legs are probably the most practically-accessible vulnerable spot, but one additional complication with that: The intended effect of a good, solid axe hit there is to make the dino fall over, but it’s probably going to fall over towards the injured side. Which is likely to be right on top of our stalwart axeman. And even without teeth or talons, an animal that big falling over on top of you is likely to be fatal in itself.

A .30-06 round has about 4kJ energy at the muzzle. A 1-ton horse moving at 20mph has about 36kJ energy. A .50 BMG round is still less than half that energy. A 20mm Vulcan round has around 54kJ muzzle energy.

Yes and with that kind of energy a wooden lance would shatter on impact with thick bone and the knight would very likely be driven off his horse. So a whole lot of that energy would evaporate without being transferred into the animal. Or, consider the angle of attack. To hit the T. Rex’s heart, the only way to kill it quickly, the knight would have to angle the lance up steeply causing much of that energy to travel on a plane away from the tip of the lance and be lost. A high-caliber round, however, would rip right through any bone and tumble through the organs.

It’s worth noting, though, that knights didn’t take out mammoths on a regular basis. A lot of mammoth hunting involved spears, traps and running them off of cliffs - in other words, the kind of dirty tricks and mass tactics that have been suggested. The knight’s footmen will be more effective than the knight himself.

As someone said above, hand-propelled harpoons managed to penetrate whales easily enough. I think your overestimating the rigidity of bone and tissue.

(also, the T-rex skeletons I’ve seen don’t have much in the way of bone protecting the front of the abdominal cavity. So even if your lance shattered on the bones, you would’ve penetrated through the internal organs and be hitting the spine or back of the pelvis by the time you got there. That might not drop the animal right away, but I suspect it would incapacitate it enough so that it wouldn’t give chase effectively, and it would die from the would relatively quickly)