Pump Action Slingshot

[JoergS]

A true repeating slingshot crossbow was always something I knew I had to make one day. Lots of problems to be solved. How do you deal with the band twisting? How do you cleanly line up the "pouch" every time? How do you feed a ball into the pouch without jamming?

Now I have done it - the first functional repeating slingshot crossbow is reality. It "fires" 20 mm (.79") steel balls.

The weapon can be loaded with 20 "rounds" within just a few seconds. Then, a simple racking action feeds a round into the chamber and cocks the bands.

The weapon is used here to smash eight glass bottles, which is done in one uncut passage with just six shots:

http://www.youtube.com/watch?v=JOlw8RW8YGI

Jörg

 

[Bobson]

Very clever design, Mr. Sprave. Looks like a lot of fun. Have you tested the speed at the muzzle with a chronograph? And what kind of accuracy is it capable of when compared to traditional brace slingshots?

Very interesting. Great job, and thanks for the video.

 

[JoergS]

Bobson, the power depends on the rubber bands I put on. If I use my strongest bands, then 60 ft-lb can be achieved, but you have to rack the slide with both arms, pressing the stock against your chest.

For normal "pump gun style" racking, the bands should not have more draw force than 15 kg (33 lbs). This will get you about 25 ft-lb of energy.

Accuracy is good. Hard to compare it with a traditional slingshot, as very good experienced shooters can be dead accurate with one - but newbies will have a hard time hitting anything. A crossbow requires much less practice for good accuracy.

 

[SDC]

Very interesting, Joerg; it seems to me that you could do something very similar along the lines of the Chinese repeating crossbow, with a hopper or tube to hold a practically endless supply of ammunition, as long as the draw length wasn't impractibly long.
PS. I also just saw a clip of you being interviewed on a Canadian science show, on the Discovery Channel. You're famous!

 

[hso]

Joerg,

Great new slingshot.

Have you thought about putting a coil spring in your ball bearing channel to feed like a shotgun tube magazine?

 

[BRad704]

Great idea as always! I can see a vertical forearm-grip being very handy for that one. as well as some type of teflon strips for the pump action to slide on...

And the new intro/outro is great as well!

 

[Bobson]

And the new intro/outro is great as well!

Good call. I loved it, looked extremely professional, music was great. Just outstanding overall. I liked the video before I saw the repeater.

 

[LJ-MosinFreak-Buck]

Joerg,

I must say, I am truly fascinated with your design, and I'll bet you that I had just finished watching every video you have posted on your Youtube channel.

I am thoroughly impressed with your line of work, and I am happy to see so many creative designs shooting the primitive slingshot into a technological era! Kudos to you! I am quite fond of your work!

 

[Odd Job]

I like it!