SpudFiles

This is an idea I have been working on for a few days. I have an idea for a recoilless sholder mounted launcher. I got the idea from a weapons refrence book at school.

So a recoilless launcher/rifle/gun eliminates the massive recoil of a cannon so it can fire a large round from a man's sholder by using newtons third law of motion "to every action there is an equal and opposite reaction". so to eliminate the recoil a oposite force is applied by a projectile being fired from the rear as well or a back blast to equilize the forward motion of the projectile so there is almost no recoil.

So I used a back blast method to equilize the recoil by simply making a diagram of a preloaded shell with a perferated shell lined with a burst disk so a pressurized fuel inside.
<img src="http://tinypic.com/s245sw.gif">

The ammo also needs a burst disk so this method would be used.
http://www.spudfiles.com/forums/viewtopic.php?t=309

The launcher has a perferated chamber as well.
<img src="http://tinypic.com/s24dnl.gif">

I have also mede up a nother diagram this one uses the same ammo busrt disk idea but it has a burst dusk in the rear of the shell and has a locking ring that holds the shell in place and connects the firing electrodes to a sorce of a spark.
<img src="http://tinypic.com/s24nxf.gif">

The launcher locks the shell into place and the locking pins ard connected to the spark sorce.
<img src="http://tinypic.com/s25dg3.gif">

The fuel should be a powerful one like mapp and I hate to say it hydrogen and I am not shure what to use at the burst disk

that looks like it would help but probably not stop all recoil
you could use 1/16inch sheet pvc from mcmaster its fairly cheap and works well
propane and mapp are just as powerful so use propane its cheaper

Air is light weight. Ammo is heavy.
Momentum transfer is (idealy) the same.
E=.5MV^2 | P=VM
Thus, much more energy is transfered to the air than to the projectile, resulting in a punted projectile and a loud noise.

My idea I had a few months ago:
<img src="http://img.photobucket.com/albums/v611/ ... pudgun.png" border="0" alt="recoilless spudgun diagramt">

Well I got the idea from the 84mm RCL Carl-Gustaf recoilless gun and of corse they use hi-explosives in there ammunition rather than propane and I want to try it still.

i had an idea once, with a Tee like blb's but with a springloaded lead piston
resulting in forces cancel out

but, i must stress that the recoil is part of the fun of spudguns

well said, recoil can be reduced by using lighter ammo, however you will need a lot of force to move a lighter projectile with as much energy as a heavy projectile to ensure proper damage to the target, i realized this using different combinations of plastic to mold slugs for air cannons

You need to use pretty light ammo before you start losing large amounts of muzzle energy, at least with a cannon that's well supplyed by valve flow.

"spring loaded lead piston"
Is not acctualy recoilless - it's just delayed recoil. May be usefull for shoulder-mounted launchers, but not much else.

"high explosives in their ammo"
Acctualy, all barreled projectile launchers (that I know of) use low explosives as the propelent charge. The difference being that we have maybe 5 grams of air, compared to 400 for the recoilless launcher you based it off. (muzzle velocity of that launcher is 300 m/s at 1.8 kg)

saladtossser wrote:i had an idea once, with a Tee like blb's but with a springloaded lead piston
resulting in forces cancel out

but, i must stress that the recoil is part of the fun of spudguns

yes saladtosser is so right. i like feeling a kick from the cannons i shoot. Unless you are using lead for ammo i dont think recoil is really a big problem.

Recoil becomes a problem in large scale cannons made from pvc pipe, the torque generated from heavy ammo at a high rate of speed can shatter barrels like glass, however this usually only happens with larger diameter pipe ( for example using large soda bottles filled with concrete & rebar in 3" or 4" pipe)

i caught a coupling in the face from recoil once. it gave me a pretty good shiner too. It was a shoulder fired propane cannon and i had my head resting on the chamber, looking down a set of sights, hit the ignition and BAM! the edge of the coupling caught me right in the cheekbone. lesson learned, dont lean your face on the cannon, or fire it from the hip hehehe

I read somewhere on this site that cartridges with the projectile and the fuel in it are considered illegal weapons. Something about them being turned into bombs or being to similiar to a real bullet. I'd check your local laws before you build this. Sorry to rain on your parade.

The rational is that it makes the spudgun a cartridge-fed weapon, and that effects the legality of the device. I forget weather this only applies to guns with a magazine or not.

And you guys saying "recoil is part of the fun"
That's an opinion, and you know it. There are people who don't like it, and cannons that even DR dislikes the recoil of.
Actualy, my design was drawn up for such a launcher - a 6" sch 40 barreled beast firing (saboted) 2L bottles full of water, that caused injuries upon launch.

Hi-explosives by our standards blb. Sorry didn't secify that

There is no shock wave formed when the NC is being consumed; so it's not a high explosive. Use the terminology correctly, or don't use it at all, and just refer to it as quick burning or such...
Which might actually be incorrect... it's probably not more than a few times quicker burning than your air-propane mixtures.

Your mocking me aren't you

boilingleadbath wrote:and cannons that even DR dislikes the recoil of.

yes, cuz he gets bumps and bruises, nobody likes that.