Killing T-Rex with a gun

I know very little about guns, ammo and/or hunting. But I’ve heard two things that seem contradictory, so I’d like some info:

(1) I’ve heard (I think on This American Life) a length and knowledgeable-seeming discussion of what kind of gun you’d need in order to kill a T-Rex if you were being attacked by one, with the consensus being “some kind of frickin’ enormous rifle, and hope you’re lucky”

(2) I’ve also read/heard various descriptions of types of bullets, such as “hollow point”, which are designed to do gruesome amount of damage to people when fired out of a pistol, ie, the entrance wound is the size of a bullet but then the exit wound is the size of a grapefruit.
So… seems to me that a fairly small gun hitting T-Rex at the center of mass could still do a relatively huge amount of damage. Say, an uzi firing hollow point bullets. If I can point it at his belly and hold the trigger down and hit him with 5 or 6 shots as he charges me, and each one punches a hole the size of a grapefruit all the way through his torso, isn’t that going to put a pretty serious hurting on him?

Pistol caliber hollowpoint bullets(which the Uzi fires) only penetrate 12-15 inches to prevent over-penetration in people. Probably won’t even reach the vitals of a T-Rex, let alone go through.

Most likely need a .50 BMG or 20mm cannon at minimum.

I know we had a thread recently on this topic.

An UZI wouldn’t do that to a man, much less a tyrannosaur. Any of the heavy rifles used for elephant and cape buffalo should be able to bring down T-Rex. You’d want to go for busting his hip or pelvis, rather than a brain shot, IMO. Tiny brain in a skull with lots of sinuses. I’d consider. 458 Winchester Magnum loaded with monolithic solids the absolute minimum gun for the job.

Previous thread.
Could I take down a T. rex with my Beretta 9mm pistol?

The Master speaks

AAAH no wonder they call you runner so fast:D

Five or six 4-5" holes all the way through would most likely mess up even a T-Rex, assuming they hit something either solid or important.

The problem is no convenient gun will put a hole like that clear through something the size of a big dinosaur. Or even a big non-dinosaur.

It takes energy to shred and displace tissue. A hollowpoint bullet expands, dumps energy quickly, but doesn’t penetrate very far. It thus makes a nasty but shallow wound. 5-6 9mm hollowpoints from an Uzi would make 5 or 6 little pockmarks in the exterior flesh and stop. Big game hunters actually tend to use non expanding or slow expanding bullets, they don’t make as big a hole, but penetrate far enough to hit vital organs or break bones.

A visualization I’ve used with some success to straighten out the folks who think a .50 BMG bullet will rip off limbs on a near miss. If this were true, and you know the round has been used to kill people a mile away… if there are 10,000 people lined up side by side with a little gap in between, 2 people per foot for a mile, and you shot a .50 in between the rows, would the bullet rip the arms off all 10,000 people? That’s a lot of power, the bullet would have to be putting that energy into the air every foot of travel eh? Makes it obviously unbelievable.

As others have said, an Uzi with 9mm hollow-point rounds is not going to penetrate the center mass of a T-Rex. If we’re talking run and gun type weapons I’d probably opt for a fully automatic medium caliber assault rifle, such as an AK-47 with some armor piercing rounds. I would feel much more comfortable with a mounted .50 cal though.

On a related note, could The Texans beat The Mexicans at The Alamo with a AK-47 if the Mexicans had a Tyrannosaurus Rex?

A handgun is extremely unlikely to take out a Grizzly bear unless you are very lucky. A T-Rex presents much more formidable problems.

L. Sprague de Camp in his famous A Gun for a Dinosaur argued for elephant guns like the .600 Nitro Express :). Of course he was writing many decades ago. No doubt there are better options today.

What are the current estimates, if any, on how fast a Rex can close on you? Aren’t most big bores bolt action, or single shot? I’d want the BMG .50 semi-auto unless I can have a mini gun and a flying pony.

Exit wounds are typically larger than entrance wounds as a result of the bullet tumbling on its axis and/or deforming while traveling through the body.

What do modern elephant poachers in places like, e.g. Kenya, use? AKs come to mind and the 7.62X39mm is a dog ballistically. Of course, they’re dumping the entire mag or belt into the critter… Maybe they’re using G3s with 7.62X51, which is still way below what I’d use on my mythical African safari. The point is that a ton of small holes have a way of evening out with a few good holes.

If I were to hunt T. Rex, I believe in the previous thread I picked something explosive, that could break down its limbs while I waited for it to bleed out. Something like Raufoss ammo, if I’m limited to something pseudo-man portable.

The thing with reptiles is I’m not sure how fast their bodies know that their heads are destroyed. A brain/spine shot “should” take down a mammal quickly (at least all of my Capstick reading seems to think so), but I’m not so sanguine about stopping a reptile.

If someone had just done this back in about 1971 we might have avoided the whole glam rock thing!

Would the best way to immobilise one be to aim for the tendons?

I’d take a flamethrower. Shooting it with anything smaller than a bazooka would be a bit chancy. A rifle might well inflict a fatal wound, but is it going to chew me up before it goes down? However, I can’t see it running through a wall of flame.

In that scenario, Davy Crockett sacrifices himself by placing a stick of dynamite under his enticing coonskin cap.

Well, you could always use the .577 T- Rex cartridge. It seems made for the job. With a 750 grain projectile moving at 2460 ft/sec and 10K foot pounds of muzzle energy and a recoil that seems entirely unreasonable.:eek:



Rather than the Nitro Express, try a chinese-jingal-wall-gun

Good answer, Sir.