Something I was thinking about

[Jack_Hogg]

Hi there,

Its been a while since I've been on here, but there are always those periods I am thinking about a idea. I was wondering if there is a posibility to make a recoilless hi-power arrow gun. The idea came from the stakegun in the game "Painkiller".

In order to manage this, I have thought of this:


The arrow plus all of its moving components ontop of the gun should be the same weight as on the other side of the cable, wich is the piston ram, and its parts. Low as possible friction for the moving parts, and the piston fired by QEV en pilotted by a 2/3 way-valve for high preformance. The acceleration of the arrow and the piston are equal, yet bi-directional. Therefor the forces work against eachother wich result is a rifle that can shoot quite heavy arrows with almost no recoil.

What do you think?

[jackssmirkingrevenge]

Look who's still lurking

Not going to get much performance with all that crap the air has to push.

A simple disk sabot will do:

[youtube][/youtube]

If you're worried about recoil, countermass, armbrust style

[Technician1002]

The original plan fails when you try to stop the counter mass. Works if it keeps going, but not if it comes to a stop.

[jackssmirkingrevenge]

Have a look at the work of your fellow Dutchman: http://www.spudfiles.com/pneumatic-cann ... 19729.html

[wyz2285]

He is talking about recoilless, not noiseless.
Instead of all that trouble, why not just a gas ram pushing the arrow?

[Talk]

Maybe you can do this to remove some of the extra stuff you used there

[dart guy]

It seem talk has a point, I would just make a stock with a rubber buttpad made of about 3 layers .

[jackssmirkingrevenge]

He is talking about recoilless, not noiseless.

That it is noiseless is serendipitous, regardless it is a good way to launch a rod like projectile. Also, not releasing the propelling gasses cuts down on recoil... in fact you could duct them to flow towards the rear of the launcher to counteract recoil

Instead of all that trouble, why not just a gas ram pushing the arrow?

Pretty much how pneumatic spearguns work.

[wyz2285]

Arrows have some considerable mass, the exhaust gas is insignificant to cause recoil. Dry fire my 3/4 piston with 500 psi cause much less recoil than launch a standard bow arrow with 3/8 port QEV with 200 psi and less chamber volume.

[jackssmirkingrevenge]

Arrows have some considerable mass, the exhaust gas is insignificant to cause recoil. Dry fire my 3/4 piston with 500 psi cause much less recoil than launch a standard bow arrow with 3/8 port QEV with 200 psi and less chamber volume.

Let's say you have 500mL at 500 psi, that's about 20 grams of air... thats about what a typical .454 Casull bullet weighs, not an inconsiderable amount. Turn that around to face the shooter and you have something much more effective than a muzzle brake because all the air comes out in the opposite direction of the projectile travel.

[youtube][/youtube]

Having seen the launcher Jack wants to replicate, I can see where he's coming from.

[wyz2285]

Forgot to mention, the 3/4 piston it's a lot heavier than the 3/8, so I can't argue much

[Brian the brain]

With a captive piston and an arrow i doublt you'll have the "recoil" you've had with your 40 bar launcher and a solid lead slug...


Because on top of the actual recoil ( gun pushes projectile and vice versa) you also feel propulsion.The jet of air pushing out of the barrel acts like a rocket engine pushing out exhaust gasses.
This will not be felt if air doesn't leave the barrel.
Furthermore: the captive piston hits the stopper at the end of the barrel, jerking the launcher forward a bit.

If things are still to rough for you, you could fill a tank connected to your exhaustvalve with water ( and sand to give it more weight) and have it eject it's contents in the opposite direction...

It'll be like a bottlerocket pushing against the recoil.