Firearm education part 1

In the wake of the Sandy Hook tragedy, people have taken to the intarwebs armed with their talking points. Talking heads have babbled about things they don't understand and the populace at large has latched on to a few too many parts of that babble.  Without taking a side on the gun control argument, I want to help out those of you who don't understand even the basics of firearms.  Why?  Because if we want to have a conversation about this, we need to know what we're talking about.  No matter how valid your stance on the issue is, if you sound like an idiot, nobody will take you seriously.

Clip vs. Magazine
This is probably the least important issue I'll touch on in regards to how firearms impact our lives.  I'm putting it first because it's so easy to get right and gun control advocates rarely do.  This makes them look silly.  Short version- When in doubt, it's a magazine, not a clip.  Few if any modern firearms use clips so just say mag or magazine because there's about a 90% chance you'll be right.  If you say clip, you have about a 3% chance of being right.  That other 7% is made up of revolvers, belt-fed weapons, and single-round weapons.
So what's the difference?  Put simply, a clip moves with the cartridges (Or bullets for those of you not worried about being exact.) while a magazine uses a spring or some other device to push the cartridges through the device. Modern weapons (and MANY older ones) use a magazine almost exclusively.  Don't say clip, you'll almost certainly sound ignorant.
Here is a decent video about it.

Armor piercing rounds
This mistake happens less often but it's a HUGE issue because it turns normal people into villains. A lot of gun control advocates admit that the right to a firearm for self defense inside the house is acceptable.

The most common round used for home defense is a hollow point or JHP (jacketed hollow point) round. These are designed to spread out on impact and transfer as much energy from the bullet into the target as possible.

A normal FMJ (full metal jacket) round can go right through soft things like muscle and keep most of their energy for themselves which defeats their purpose in a defense situation. They are cleaner to fire and cheaper and are thus the preferred round for target practice and shooting ranges

Armor piercing rounds are designed to penetrate armor- metal, composite, fabric... As you can see, they have a fine, pointed tip that concentrates their energy on a very small area.

Why does this matter?  The news and the blogosphere frequently obfuscate this by referring to various bullets as "cop killers" or by noting that armor piercing rounds make a gunman more dangerous.  The fact of the matter is that each different type of bullet is very useful in some situations and next to useless in others.  Against your average burglar wearing sweats or jeans, a hollow point is ideal as it imparts maximum energy on the target. FMJ rounds will do a lot of damage but a higher powered one will go right through a person and possibly through the wall behind them if it doesn't hit something like a bone or a stud. An AP round will almost always go right through something as soft as a person without any fragmentation at all. This means that if you are protecting your house with AP rounds, you are putting your neighbors in danger because the bullet COULD go right through your walls and into your neighbor's house.

Semi-automatic?
There are three basic types of gun in this regard.
1. Standard fire (bolt-action, many shotguns, and the like) weapons can be fired one time per pull of the trigger and between trigger pulls, you must manually reload and re-cock the weapon. Think about the shotguns in most movies.  You pull the trigger, you pump it, you pull again...
2. Semi-automatic weapons fire one round per trigger pull but use the recoil of the shot to chamber another round and cock the hammer. This means that you can fire almost as quickly as you can pull the trigger. Think of almost every handgun you've ever seen.
3. Fully automatic weapons are like semi-auto in that they use the recoil to chamber the round and cock the hammer but they will continue to fire if you simply hold the trigger down- think machine guns the army uses.

Confusing semi-auto (at this point, the standard weapon system for civilians) with full-auto weapons (standard system for the military) is a pretty major mistake as semi-auto is common and full-auto is, in the US, illegal for normal citizens to have. Thus there's a pretty big difference between a fully automatic weapon and a semi-automatic weapon from the legal and philosophical standpoint.

While I have VERY strong opinions on firearms ownership (probably not what you think though...), I'm more interested in sharing the knowledge I've gathered with those who want it.  We can't have a reasoned debate if people don't actually know what they're saying.