Well a TEC-9 can be a machine-gun by the basic dictionary or the US legal meaning of a firearm shooting more than one bullet with a pull of the trigger.

Also the 'perception' of mags being clips and so on is reality because it is very prolific. Not so much "tec-9 machinegun, m1 garand assault rifle". If I picked a random individual on the street he or she would likely not even know what a tec 9 or a m1 garand is. Also if said person knew of these firearms by name, more likely than not they would know that said firearm is not an mg or assault rifle.

Well, sure, but the actual meaning of the words doesn't match common usage. That's not really uncommon (for example, it's really common to call a weapon system like Phalanx a "turret" when it's correctly called an "installation" since it doesn't cross the armour of the thing it's mounted on) and in conversation as long as the person you're talking to understands what you mean it doesn't matter, but it's still not correct.

While I'd agree obsessing over it isn't good and people go overboard, it's the same question as if someone you know is trying to use deodorant to cover that they haven't washed (and failing). Sure, they might take offence if you tell them, or they might honestly not know it isn't working and be glad you saved them embarassing themselves. And in the end it isn't your fault for pointing it out unless you're a dick about doing so.

Well, it's more that someone who uses a weapon for a living doesn't really have to care too much about what the correct terms are for the various bits of it. For, say, the guy at the depot trying to work out if the guys on the front want thirty cases of preloaded mags or thirty cases of stripper clips, then it's a bit more of an issue. (Let's not even get into things like what ground crews think of pilots' knowledge of their aircraft).

Well yeah, but by the US legal meaning a sear can be a machine gun, even though a sear isn't a gun at all.

That's not exactly quantifiable.

Of a block of metal with a S/N stamped on it that has a Tax stamp associated with it. Remember when the ATF tried to declare a 'shoelace' when tied to the trigger of a weapon whose vibration would initiate another firing pin actuation, to be a machine gun. Yes, a SHOELACE would be a machine gun if attached to a semiauto rifle. Either way that is WHY no historian or scholar would use the Lawyer's definition of a machine gun.

According to government lawyers, if you spill a bunch of water on your own property and don't drain it in less than 30 days, that property magically becomes a 'wetland' and is protected by the EPA. Doesn't matter that NO environmental scientist or botanist or whatever would EVER even look at that land as a 'wetland'.

Acceding to Lawyer speak in this realm means giving in to 'crazy town' definitions.

Never heard of preloaded mags coming straight from the depot.

I'm playing devil's advocate and yeah it's incorrect practice to call a mag a clip.
I just think it's obnoxious to snap on someone for something small like that.

As I recall, wasn't the reason that failed because a shoelace would be a machine gun even if it wasn't attached to the rifle? I guess they were hoping that by now America would be free of everything but grandfathered shoelaces and they could get on to tackling the threat of velcro.

I thought I'd heard of it being done, though I can see why you wouldn't, it's just asking for springs to fail on you. Still, just empty mags would be the same problem if you wind up with 30 cans of them when you wanted 30 cans of bullets.

Well, depends on usage, really. If you discuss things at a technical level a lot you need the terms to mean different things since otherwise it's rather hard to explain, say, what the difference is between a Mauser C96 and an M712 (one uses a 10-round clip and the other uses...a 10-round clip? A 10-round detachable clip? But, um, isn't the first one's clip...argh). Obviously the "perception" argument doesn't apply to the things themselves; if you put a C96 clip and a Schnellfeuer box magazine on the table side by side, no matter who looks at them it will be clear they are two different things. The trouble is the common usage leaves no word to describe one but not the other.

To give the example I should have given to begin with, "chaingun" is a good example of a term almonst universally used incorrectly. You ask your average man on the street what a chaingun is and you'll almost certainly have a gatling gun described to you. Which is fine until you're trying to explain what kind of gun a Bradley has and realise the actual term for it doesn't mean what it's supposed to anymore.

Maybe it is a regional thing (I'm from England) but I have never heard someone refer to a rifle magazine as a clip, only pistol magazines. Also soldiers today definitely know the difference between a magazine and a clip, otherwise you would get situations like you carry 8 clips in your webbing and 15 clips in a bandolier and to fill up a clip you empty 3 clips into it. This is just my personal opinion, but I've always thought that the reason clip is used rather than magazine is because it is a "cooler" sounding word, so gets overused (relative to the correct term magazine) in films, television and music, leading to people thinking it is the correct term. Personally I won't correct someone if they use the term incorrectly in conversation, I will just take that as a cue that I probably know more about the subject than them.