« Nilsson | Main | Who Says Green Jobs Don't Pay Well? »

Everything I Know About Firearms I Learned From Police Academy 2

May 6, 2009 | Permalink

Comments

I was just reading about features of different ammo types the other day. I guess .45 have a lower velocity, so they're not useful for things like penetrating armor or long range accuracy. But if you shoot a side of beef, you'll notice a larger-diameter impact than other ammo types. That's "stopping power". Not so good cracking the engine block of a truck. I guess a .357 (there are a couple types right?) works for that but I don't know.

Posted by: tpulley | May 7, 2009 3:43:56 AM

tpulley,

That's basically right. Since F=ma (Force = mass x acceleration), all else being equal, a faster bullet has more force. However, the .45 is widely regarded as the best person-stopping round. I believe that part of the reason is that due to its lower velocity, the bullet is less likely to pass through its target, and by not passing through, it delivers more of its energy (i.e., Force) to the target.

The issue of transferring the energy of the shot to the target is why many people who carry concealed weapons choose frangible rounds (i.e., those that break up on impact). More damage to Bad Guys = greater chance of survival of Good Guys.

Posted by: Sparticus | May 8, 2009 5:14:51 PM

Well, force is one thing, but the equation for kinetic energy is 1/2*m*v^2, so even small objects increase KE exponentially as velocity increases linearly. That's why orbital space debris is such a looming problem.

What I read is that .45 doesn't penetrate body armor (or relatively light steel), but it would certainly push a person back no matter how much armor/padding they had.

I heard that frangible bullets are good for avoiding ricochet in places where that would be desirable. Then there's soft point and hollow point rounds that expand upon impact, broadening and reducing penetration.

A .357 magnum will not crack the engine block of a truck. but a .44 magnum will.

Posted by: tpulley | May 9, 2009 9:10:04 AM

Yes, I'd forgotten about the kinetic energy equation, which explains why a bullet can be so much more deadly than, say, a car.

Frangible bullets are also good in the home, because they don't penetrate walls, meaning that they also don't penetrate your family members on the other sides of those walls.

.44 magnums are hand-held cannons.

Posted by: Sparticus | May 9, 2009 11:10:34 PM

> I heard that frangible bullets are good for avoiding ricochet in places where that would be desirable.

Such as airplanes in flight... Yes.

> Yes, I'd forgotten about the kinetic energy equation, which explains why a bullet can be so much more deadly than, say, a car.

Not if the car is used *properly*

:oP

Seriously -- I'm waiting for the day when a terrorist attack involves using a car "properly". I shan't comment more on the idea until that day, though.

Posted by: O Bloody Hell | May 13, 2009 10:54:48 PM

The comments to this entry are closed.