In the TV series House, M.D. episode " The Dig", House is attending a spud gun show with Thirteen, where he uses the spud gun to threaten a teenage competitor who taunts House. Notwithstanding all the other contributors, your pipe is a firearm under British law. It is an offence to discharge it near a highway. This is not a Health and Safety regulation or a civil law, it is the criminal law. Any combustion cannon with a potential muzzle energy of greater than 1 ft-lb (it may be 1 Joule, I forget) will fit into one of these groups.

I have heard of people being given clips on the ear for it, and even some cases of the armed response unit being called, which may well have included arrests, but bear in mind, that relates just to people I've spoken to on the internet - a very small minority, and generally a more sensible one, and if even they can get the ARU on them... Heating the gases to far higher temperatures, and thus giving them more energy. This allows hybrids and combustions to achieve supersonic velocities. The law on AIR GUNS has just changed, and there are now age limits. Tresspass with an air gun is criminal tresspass.

It's very hard to tie any instances of spudgun arrests in news reports, as they prefer to refer to "homemade weapons", rather than "Spudguns", because say spudgun to most people in this country, and they think small kids toy, and the media and police like to play things up - to get the audience's attention, and to look good respectively. Van Horn, Dale R. (October 1932). "Perform These STARTLING STUNTS with DRY ICE". Modern Mechanix and Inventions: 114–116 . Retrieved 15 August 2011. Pneumatic line throwers for launching lines for rescue missions or between ships for replenishment at sea as well as a number of other applications. Both PVC and ABS piping are also available in forms that are not pressure rated. The use of unrated plastic piping and fittings is a common source of cannon failure and poses a much greater risk to a cannon operator. Users should follow the same rules as if handling a conventional firearm (see gun safety), but given the frequently improvised materials and construction used in spudguns, it is particularly important for the user to use basic ear and eye protection when operating a spudgun.

The dry ice bomb used for propulsion can achieve bursting pressure in a matter of seconds to hours depending on the quantity of water and dry ice. If too little dry ice, it also may not achieve bursting pressure at all. These timing issues can cause belief that the cannon has failed to fire but attempting to unload the cannon may then provide the extra stress on the bottle needed for it to rupture. An extremely high-velocity potato cannon is featured as a project from Nelson "Big Head" Bighetti in Silicon Valley (season 2). By the combustion of a pre-pressurised fuel-air mixture; this is called a hybrid launcher, and yields higher pressures than that of a normal combustion spud gun, limited only by the construction of the launcher (generally a few hundred pounds-force per square inch). The video game Scrap Mechanic has 4 variants of spud guns: a single shot spud gun, a double barrel spud shot gun which fires French fries, a 'spudling' gun which is a triple barrel Gatling gun, and a mountable spud gun which can be mounted on your creations. Rejoice! Biker season is more than halfway through. For months now, hundreds of leather-clad knights of the road have been mounting their silencer-free steel-and-chrome stallions and setting off at first light into the countryside in search of suitable stretches of Tarmac. And, as dawn breaks over villages and hamlets, residents are woken by the nerve-jangling scream of a hundred high-powered Kawahozki 900s as they blast along the winding A roads, their riders unaware of – or unconcerned by – the sound footprint being dragged through rural dreams.Didymus, JohnThomas (2013-02-06). "Video: Supersonic Ping-Pong gun fires a ball faster than sound". Digital Journal . Retrieved 2013-10-21. By the release of compressed gas (normally air) through a valve; such a launcher is typically referred to as a pneumatic launcher, and its power is limited primarily by the pressure of the air supply, be that from a compressor, manual pump or bottled gas. Pneumatic launchers are considered a little more difficult to build due to the need of a completely airtight construction. These cannons have four basic components: The highest projectile speed recorded from a spud gun is 933.3m/s (3,062ft/s) (approximately 2.7 times the speed of sound) with a 16.6-gram (256gr) 20mm plastic slug from a hybrid using a 20MPa (2,900psi) pre-ignition mixture of air and propane. [22] How legal is this device? Would it be considered a firearm, as it 'fires' ? Is it no more legal than going to a park and igniting hairspray using matches, even though this all happens in a confined area?

Sprinkler valve (otherwise known as a solenoid valve): The use of irrigation sprinkler valves as pneumatic valves has become increasingly popular for spudgunning. These valves are intended to be electrically triggered causing a solenoid to depressurise a diaphragm and allow airflow through. It is also possible to remove the solenoid and, instead, to actuate the valve manually with a blowgun to depressurise the diaphragm. Such modifications allow the valve to open as much as 3 to 5 times faster. New stuff". The Spudgun Technology Center. 14 January 2010 [6 July 2002] . Retrieved 16 August 2011.Ball Valve: Made out of either plastic or metal, ball valves are considered inferior by many enthusiasts due to their slow opening times. For those on a tight budget or in low-power setups, ball valves are ideal. Some choose to modify their valves by attaching a pneumatic actuator or spring to achieve a faster opening speed. Threaded Fittings: commonly available in BSP or NPT (not interchangeable) they generally require a fitting attached to a pipe by other means to allow screwing into another threaded fitting. The exception to this is steel pipe, the ends of which can have the appropriate thread cut into them. In spite of what you say about your land being in the middle of nowhere, someone will own it and someone will have access rights to it although,I admit, maybe not the public. Perhaps you can get the landowner's permission to fire your cannon on it. Even then you have a duty of care to ensure there are no third party injuries or damage. Someone (and you admit it may be you) will inevitably get hurt. a b BigBang (October 2006). "Crusader". SpudFiles. Archived from the original on 20 February 2009 . Retrieved 2009-06-01.

Dwight Schrute on the U.S. version of The Office has mentioned owning a spud gun in more than one episode. Duct tape: sometimes used in simple cannons, it is unsuitable for sealing any significant pneumatic pressure and if used on a combustion cannon the heat produced can soften the adhesive and melt the tape, greatly weakening any seal or joint it creates. In a pneumatic spud gun, air is pumped into the pressure chamber. After the desired chamber pressure is reached, the pressure release valve is opened, allowing the gas to expand down the barrel, propelling the projectile forwards. It is almost certainly a firearm under UK law. It uses expanding hot gas to fire a projectile. But it would seem that if you aren't stupid with it and you only fire it in the middle of nowhere, most people will turn a blind eye to it (not the best phrase to use I know). I used to work in the firework industry where there are lots of laws written down by the Health & Safety Executive, and to be honest nobody still knows for sure what they can and can't do. So getting a definitive answer for something that is in a very grey area will be nearly impossible.In Germany, a spud gun does not differ legally from any other firearm (for ones that use combustion to propel the projectile) or air rifle. The manufacture, acquisition and possession is therefore subject to the same requirements as for any other weapon of the same category. Since there is no known model developed before 1871, which would classify that model as an antique, spud guns are not subject to the eased regulations regarding antique weapons. Therefore any non-combusting spud gun with a maximum projectile energy of 7.5 joules can be owned by anyone without a license, while their manufacture still requires one. The legal possession of any other such weapon requires a gun license.