SpudFiles

Here's a bit of a blast from the past - this is "The beast" - so named because compared to my other projects, it was the biggest and most powerful launcher I had made, this was *gasp* 2001! Time flies when you're making holes in stuff

It's 10mm (about 0.39") calibre, and works like an exhaust valve piston, in the sense that it's a barrel sealer, which is actuated by the air in the chamber pushing a piston back to allow air to escape through the barrel. The different is that instead of being held against the barrel by air pressure in a pilot chamber, the piston is held in place by a latch that doubles as a trigger. The piston in this case was made by cutting down and reinforcing the plunger of a 20mL syringe.

The advantage of this system is that actuation is instant when compared to having a pilot chamber, though of course you're limited to the amount of pressure you can use before it begins to leak, I rarely went above 100 psi. also, the piston acceleration is very violent and needs a bumper to keep it from flying out and hitting you in the face.

You might note the amount features I added, like an integral suppressor that is very effective, and the very ergonomic handle (that came off a toy shotgun) as well as the detachable shoulder stock. I also fitted open sights to assist with aiming, I made the rear sight adjustable using a bolt and three nuts - basically, the "notch" in the sight is the space between the two central nuts, that's adjustable for windage (left and right) by simply turning the bolt clockwise or anticlockwise.

For more detailed information on using epoxy, check out the how-tos here and here.

thats a mad way of venting the pistion and it dosnt look to bad (just a bit getto) and the ajustable sghts are awsome

nice work great gun 8)

Looks cool! I like the pistol grip, The idea on the adjustable rear site is sweet. Is it accurate?

With consistent ammo (10mm ball bearings) I could hit a 3.5" floppy disk reliably at 20 yards, which is about the best accuracy you can expect from an improvised launcher with a smoothbore barrel.

That is pretty good then. I might have to make a pneumatic, haven't tryed to yet, still working on my first real combustion cannon but soldering copper is a problem I don't know how to yet. But pvc can do the same thing if I am correct. Mabe even steel pipe?

I like looks like real fun! get your self down to a gun smith and get the barrel riffeled then see what fun you have....

Bubba

Thats a pretty slick rifle. I really like the adjustable sights, they're a nice touch. I'm starting to sway mor in the dirction of small-bore, high power rifles myself. My .40 cal. QEV gun is in the works right now

Dang thats one heluva good looking gun.

That looks pretty cool, looks like the Benelli M4shotgun with the skeleton stock.

Also, I thought caliber was only in inches.

That is pretty close but its just not as big off stock.

COD_FILLETS wrote:Also, I thought caliber was only in inches.

Depends what part of the world you're in, in the US your M16's a 0.223", but in Europe it would be 5.56mm calibre

Very nice! That's a sweet sight, too. I'm curious about how you made the suppressor so effective. Have you tested it w/ and w/o to hear the difference?

Also, I'm confused about how your piston works. It looks like the gun is a coaxial. I assume the air pressure is only on the left side of that plug with the piston cylinder in it. Do you have a stop that keeps the piston from leaving the the syringe tube it slides in? It seems like you'd need that to keep all the air from just venting out the back there, and also so that you wouldn't have to manually re-insert the piston in the tube every shot!

Ladies and gentlemen Jack has done it again...I think

jackssmirkingrevenge wrote:Depends what part of the world you're in, in the US your M16's a 0.223", but in Europe it would be 5.56mm calibre

Never really cared much for the subtle differences between -er and -re endings.

That is a nice idea for piston actuation........ will that work for larger pistons? i might have to make a piston valve actuated by a pneumatic ram.......