Is a mass driver/railgun/coilgun legally considered a gun?

This is just out of sheer curiosity, honest.

I know it probably depends upon state (I’m in Arizona) but I’m wondering generally, non-US country definitions welcome too.

Most legal definitions I can find specify an explosive propulsion mechanism of some sort. Now I have no doubts that if I (somehow) managed to build a feasible projectile-firing railgun, coilgun, or any other electromagnetic propulsion device and carry it around the cops aren’t going to particularly CARE what the legal definition is, but it’s really hard to find anything on this. My searches all return research stuff from various universities, and “Mass Driver weapon legality” returns… stuff about driving in Massachusetts and cops. :smack:

My guess, so you know my reasoning in order to correct me/confirm me: Anyone arguing the case worth his salt is going to point out that “explosion” doesn’t necessarily include gas expansion and temperature increase, but rather that excessive magnetic pressure is a perfectly valid form of explosion (“magnetic explosion”). But I’m not sure that’s what they had in mind when they actually wrote the law, which is what is leaving me scratching my head.

Final Thought: Does explosive mean anything that creates an explosion or does it have a much more specific substance definition when dealing with demolitions/firearms?

Bonus Question: If it IS a gun… well I’m still confused. From what I understand, in the US you have to be over 21, not convicted of any felonies, and wait a small waiting period in most (all?) areas… but that’s purchasing a firearm. If I’m making a [del]physics experiment[/del] non-typical gun from scratch, is there any special provision as far as that goes?

I have no idea what made me think of this question (and no, I know NOTHING about gun regulation making my post confusing as hell, sorry 'bout that), but fire away. -snerk-

It would be a “firearm” in Canada, as set out in the definition in the Criminal Code, which doesn’t require any explosion:

I don’t think that it makes it legal if you make it yourself. I recall a case a while back ( I can’t find a link to the story ) about a guy who made a fully automatic weapon from ( among other things ) chainsaw parts; it was confiscated because civilians aren’t supposed to have machineguns, homemade or not.

You need a Class II license to make your own firearms. Fortunately, rail guns are not firearms. Go have a blast.

I don’t know about the BATF, but if you discharge an electromagnetically propelled weapon the FCC will be all over your ass.



Class II is for NFA weapons. For non-NFA weapons, I believe Class I is sufficient.


The BATFE generally does not require you to have a license to make a firearm provided you are not making it for sale. Cite.
The key point for this discussion is what the terms firearm and gun mean.

The BATFE defines a firearm as

Cite. (PDF)

Sometimes there are peculiarities in the laws. Blackpowder rifles, shotguns, and revolvers aren’t legally considered guns for purposes of commerce. They can be freely bought and sold without a background check, purchased mailorder, over the web, and so on. Check the Dixie Gun Works website for a metric assload of examples.

For purposes of criminal law, a blackpowder revolver is just as much a weapon as a Glock.

So, you don’t need a license to build a railgun. BATFE doesn’t define it as a firearm. If you illegally shoot somebody with it, you’ll be in just the same trouble as if you’d used a conventional gun.

I don’t know, but if you managed to design and build a man-portable mass driver/railgun/coilgun/gausegun, I’m sure you’d be able to retire wealthy on fat defense contracts.

Civilians aren’t supposed to have unregistered machine guns. Unfortunately, the registry was closed in '86, so civilians are restricted to buying from the limited pool of machine guns that’re already registered.

Regardless, your example isn’t really relevant to a non-fully automatic mass driver since machine guns are given special treatment under the law. The ATF gets really upset when it comes to illegal machine guns.

Class I is an importer of NFA weapons. Class II is a manufacturer of NFA weapons. Class III is a dealer of NFA weapons. All of the class designations refer to the Special Operations Tax (SOT) specifically for dealing with NFA stuff.

What you’re looking for is a type 7 FFL. That’s a regular manufacturer.

Also, I believe there are provisions to allow a private individual to manufacture their own firearm. I don’t recall the details since I wasn’t paying too much attention, but I’ve heard people talk about being able to legally buy a parts kit and then building their own receiver from sheet metal.

I vaguely seem to recall that the important distinction to make it legal is that the individual does not do this with the intent of selling the firearm. I believe they can sell it at some arbitrary point in the future if they decide to get rid of it, they just can’t build it with the intent of selling it. Also, I believe they have to stamp their name and a serial number of the receiver as the builder. However, you should not attempt this based on my vague information – consider this just enough casual advice to know that it may be worth reading up on.

Regardless, this is getting away from the mass driver issue. I’m not sure that the ATF would even consider it a firearm, which makes the federal issue moot. It’d depend on their definition, though.

Edit: And it looks like Scumpup answered the definition issue. Thanks.

Der Trihs lives in California.


An explosive is any substance that is capable of combusting at faster than the bulk speed of sound in that material. Gunpowder is more accurately an energetic material, as even under confinement it generally doesn’t explode, it deflagrates. The way I understand it, deflagrations are more consistent at generally accepted manufacturing tolerances; it would be too expensive to manufacture a round using actual explosives (not to mention how sturdy you would have to make the breech!). I believe the primer, on the other hand, is actually a primary explosive, though.

Does a railgun have an actual barrel, though?

“(D) any destructive device.”

So, hammers are firearms? I did not know that.

In California…

I don’t think it would be a gun. I am going on my recent experience on a jury. The case involved an item that was for all intents and purposes a hand gun. It looked like a hand gun; a police officer testified that he made his arrest assuming it was a hand gun; it fires metallic projectiles at high velocity; it was used (purportedly) to shoot out car windows.

But, the lawyers and the judge were very careful to never ever call the thing a gun. Why? Because the propellent was CO[sub]2[/sub], not powder.

It made for terribly awkward sentences.

If you go to the link I provided, BATFE also define what they mean by the term “destructive device.” For their purposes, a hammer is not a destructive device.

The definition of ‘Destructive Device’ includes

This raises the question of whether or not electricity is considered a propellant. And no, they don’t define propellant.

We’ll have to see Jragon’s specs for his new invention before we can judge it. :slight_smile:

Unless you tie it to a hand grenade.

Pellet guns and airsoft guns are not considered firearms, whether they are powered by air, CO2, springs, or motors.

Spud guns are not considered firearms, and you can make them yourself, even though most of them do use flammable chemical propellant.

Flare launchers are also not considered firearms.

So, from what I’m getting, “No… just don’t shoot someone in the face with it.”

Alright then! Gets out the screwdriver :stuck_out_tongue:

[[Disclaimer: I am fully aware of attempts to make a feasible railgun and the associated complications, I am not about to attempt to do what probably several hundred military funded researchers could not, good day.]]