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Has a coilgun a barrel or not??

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DerAlbi

Wed Jun 03 2015, 06:43AM

Registered Member #2906 Joined: Sun Jun 06 2010, 02:20AM
Location: Dresden, Germany
Posts: 727

Hi guys,
while i am working on the redesign of my coilgun i did some research due to legal issues with a powerfull coilgun.
I read the German law and also some basics of the UK law.... and it basically comes down to the fact if the coilgun fits the definition in the laws by having a barrel or not. Guns are in both laws "barreled devices" and i really dont know if to fear such definition or to smile on it.

In my understanding the coilgun does not have a typical weapon barrel since a barrel is used to compress and direct the expanding gasses and guide the projectile. It is true that most coilgun use tubes as "barrel" however its technically not needed and more of a coil protection and it does not guide the projectile since the projectile follows the magnetic field, not the barrel. And Air-Core-Solenoids cant really count as a weapon-barrel since that would cripple every linear motor

I know that legal issues have been discussed here. However since ive got such advances in energy density and efficiency so that a commercial design would be possible, the whole legal stuff is a whole new game level. Noone cares about a private hobbyist, but starting a company selling an electromagnetic gun, as strong as the strongest crossbows but with 3 shots per second is another thing.

Thats why i need a good and solid argument why weapon definitions do apply or not apply (i am open for both, however i like to hear "not apply". Of course it would (economically) be an advantage to avoid legal issues and be free to sell to unlicenced customers). However i am not an unmoral person... sice coilguns (due to the slow subsonic projectiel speed) will never find millitary use (at least not my design) and the pure formfactor makes it impractical to concile or to mug someone and long range assault is basically impossible too, i would be ok to sell to everyone who has a driving licence for example. everone who is responsible enough not to drive on the sidewalk on a mass murder killing spree can handle a dangerous toy like a coilgun.

I would define coilguns currently to be a gray zone in most laws.
While in germany the gray is quite light, the gray in th UK is quite dark... if you know other countries definitions, i would like to hear from it

Specially US, since i see quite a customer crowd there - even when beeing force to sell only to licenced people)
And of course i want to hear your argumentation about the barrel issue! (or if you have any official definitions.....?)

I know that you cant give any legal advice and in my case I will soon go to the german BKA to get a definitive answer for Germany. Still.. i want to have solid arguments... so if you can support me, please do

Dr. Slack

Wed Jun 03 2015, 07:57AM

Registered Member #72 Joined: Thu Feb 09 2006, 08:29AM
Location: UK St. Albans
Posts: 1659

One line of argument, though I am sure this would be resisted by those who wanted to ban CGs (coilguns), is to ask what the barrel in a conventional gun does. Does it merely guide the projectile, or does it take part in the propulsion by constraining the expanding gases as a cylinder round the piston that is the projectile. Obviously the latter.

Now in a CG, the barrel is merely a mechanical guide. This can be demonstrated by making it out of a number of parallel wires with spaces in between. This arrangement would obviously not work in an expanding gas gun.

Now whether the (let's call it) projectile guide in a saleable CG actually *needs* to be made of wires rather than a tube, or could be argued to have an equivalent function to, is another matter. On emotive issues like gun control, logic takes a back seat, or rather the axioms that precede the logical process are chosen rhetorically by entrenched sides with axes to grind. If the man wants to ban CGs, then I suspect even making the guide out of wires will not be sufficient argument of itself.

In fact, as a citizen, I'm not sure I'd like the 'it's a guide, not a barrel' argument to hold sway if people were able to get their hands on unlicensed things capable of throwing objects with kinetic energy exceeding X joules in my direction. Like unlicensed radio having a radiated power limit, I would like unlicensed thing throwers to have an energy limit, as well as a technical difference from guns.

DerAlbi

Wed Jun 03 2015, 08:16AM

Registered Member #2906 Joined: Sun Jun 06 2010, 02:20AM
Location: Dresden, Germany
Posts: 727

Dr. Slack wrote ...
In fact, as a citizen, I'm not sure I'd like the 'it's a guide, not a barrel' argument to hold sway if people were able to get their hands on unlicensed things capable of throwing objects with kinetic energy exceeding X joules in my direction.

I totally understand your concerns and i agree. I see it as my duty as developper/engineer to provide safety mechanisms to make the machine as unusable as a _weapon_ as possible. I do plan to include acceleration sensors to sense uncontrolled recoil (changing angle during a tripple burst and shooting too far) and to use the same accelerometer to inhibit shooting after shocks to the device (eg a supervisor sees idiotic behavoir, he just needs to kick the gun and its disabled for 3sec or when it falls or whatever.) and a remotecontrol-like IR-Tranceiver at the front could sense if you are inside somewhere or (too) close to an object to take away the easy chances for selfinflicted harm.

The truth is that devices like Crossbows allready provide projectile energies near 100J (which would be my output energy) and they are readily available for 18+ customers (at least in germany). Since i saw that, it took some concerns away from me... someone who wants to do damage with a subsonic projectile would choose a crossbow since even the expensive ones will cost only a third. (my price point for a coilgun is estimated to be 1.400â‚¬) I also think that a crossbow could actually more precice at long range and the stealthy aspect is the same as with a coilgun.
Who wants to do bad things is allready capable of it... i am not sure if the availability of coilguns will change that.

hen918

Wed Jun 03 2015, 05:33PM

Registered Member #11591 Joined: Wed Mar 20 2013, 08:20PM
Location: UK
Posts: 556

Well, I researched into UK law about guns, and found that alot of the guidance cannot apply, however a firearm is a "lethal barrelled weapon"; The Google definition of barrel: "a cylindrical tube forming part of an object such as a gun or a pen" so a powerful barrelled coilgun will probably be considered a firearm by UK law. A mandrelled coilgun, however, would not be considered a firearm.

Ash Small

Wed Jun 03 2015, 06:03PM

Registered Member #3414 Joined: Sun Nov 14 2010, 05:05PM
Location: UK
Posts: 4245

I found these two quotes:

"a component part must be a part that if it were removed, the Gun could not function without it."

So if it still launches the projectile without the barrel fitted, it doesn't have a 'barrel' as a 'compomnent part'.

"An air rifle is "specially dangerous" if it is capable of discharging a missile so that the missile has, on being discharged from the muzzle of the weapon, kinetic energy in excess in the case of a pistol of 6 ft lbs or, in the case of an air weapon other than an air pistol, 12 ft lbs: Firearms (Dangerous Air Weapons) Rules 1969 rr. 2, 3 (Archbold 24-8a.) "

and

"Unless an air weapon falls within one of the above exceptions, it is not subject to section 1 Firearms Act 1968. "

So, if it is not a 'pistol' and the projectile has an energy less than 12 ft lbs it is not a firearm.

Does your projectile have an energy of more than 12 ft lbs?

hen918

Wed Jun 03 2015, 06:19PM

Registered Member #11591 Joined: Wed Mar 20 2013, 08:20PM
Location: UK
Posts: 556

Ash Small wrote ...

I found these two quotes:

"a component part must be a part that if it were removed, the Gun could not function without it."

So if it still launches the projectile without the barrel fitted, it doesn't have a 'barrel' as a 'compomnent part'.

"An air rifle is "specially dangerous" if it is capable of discharging a missile so that the missile has, on being discharged from the muzzle of the weapon, kinetic energy in excess in the case of a pistol of 6 ft lbs or, in the case of an air weapon other than an air pistol, 12 ft lbs: Firearms (Dangerous Air Weapons) Rules 1969 rr. 2, 3 (Archbold 24-8a.) "

and

"Unless an air weapon falls within one of the above exceptions, it is not subject to section 1 Firearms Act 1968. "

So, if it is not a 'pistol' and the projectile has an energy less than 12 ft lbs it is not a firearm.

Does your projectile have an energy of more than 12 ft lbs?

But a coilgun is not an air weapon, so that doesn't apply.

Ash Small

Wed Jun 03 2015, 06:54PM

Registered Member #3414 Joined: Sun Nov 14 2010, 05:05PM
Location: UK
Posts: 4245

hen918 wrote ...

But a coilgun is not an air weapon, so that doesn't apply.

I think you'll find with most of these things that it's the energy of the projectile that is the determining factor. I just happened to remember fitting uprated springs to air rifles during my 'mis-spent youth' in order to 'gert around' the regulations.

If you can argue that an air rifle with less than 12 ft lbs projectile energy is not a firearm, then the same argument applies for other 'weapons'.

Signification

Wed Jun 03 2015, 07:06PM

Registered Member #54278 Joined: Sat Jan 17 2015, 04:42AM
Location: Amite, La.
Posts: 367

It's basically a solenoid with just a guide for the plunger---right?

hen918

Wed Jun 03 2015, 07:28PM

Registered Member #11591 Joined: Wed Mar 20 2013, 08:20PM
Location: UK
Posts: 556

Ash Small wrote ...

hen918 wrote ...

But a coilgun is not an air weapon, so that doesn't apply.

I think the law will (in the unfortunate circumstance that it's used) be taken a little more literally: It specifically stated that the 12ft pound limit applies to air weapons.
An extremely small calibre conventional gun with a power under 12 ft.lbs would be classified as a firearm.

DerAlbi

Wed Jun 03 2015, 08:41PM

Registered Member #2906 Joined: Sun Jun 06 2010, 02:20AM
Location: Dresden, Germany
Posts: 727

Wow. One takes a nap and you miss some activity here

Thanks guys for the input.
The 12 ft.lbs is similar to german regulations (where the limit is 7Joule). However this is not much of a point... since:

Does your projectile have an energy of more than 12 ft lbs?

Yes. little about 100J planned. Thats >74ft.lbs.

The energy is unfortunately not an argument... the only way i can make it legal that way is to softwaredefine the output power on delivery to that ridicules low values and make the user find out how to hack the output power to its full potential. But honestly... i dont like such shady stuff..

The question is also: wouldt it actually sell for 1.400â‚¬ (=1600$)? I think the pice is quite unattractive if you need a licence since you have access to more usable guns for lower cost. But if you dont, then there should be potential customers available. I do depend on the legal status way too much -.-

Another argument:
Is legality determined at device level oder technology level?
I mean.. i do provide a "7kW impulse linear motor". Nothing else. An electrical Motor.
While firearms (btw: there is no fire involved in a coilgun!

) use gunpowder as propulsion.... I think thats currently one of the main distiushing features.. Airsoft vs "real guns" and so on.. every guntype has its own regulations. But there is no regulation for Coilguns, so its currently undefined...? maybe?

Edit: Thats basically what hen says:

I think the law will (in the unfortunate circumstance that it's used) be taken a little more literally: It specifically stated that the 12ft pound limit applies to air weapons.
An extremely small calibre conventional gun with a power under 12 ft.lbs would be classified as a firearm.

Fortunately its neither an airsoft nor a firearm. Its a Motor.

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