Hello all - see my best slingshot crossbows

Hello,

let me introduce myself first, I am Jörg Sprave, 46 years of age, a German. I run "The Slingshot Channel" on youtube, a hobby I am very proud off. Now that Ivo (whom I met before on another great forum - Hi Ivo!) has officially declared rubber to be an established energy "source" for crossbows, it seems it is time for me to start posting here.

I have designed and built many slingshot crossbows in the last few years, but here are two designs that work really well.

First, my "medieval style" crossbow - with draw weights of up to 200 lbs, a mighty strong ball shooting weapon.



The lock is a modified "rolling nut" that can accomodate a 19mm (.75") lead ball, large musket ammo in fact.



I use spear gun rubber for it, quickly interchangeable.



Here are two videos about it:

With 100 lbs bands, no scope:



200 lbs, at last:



The other model is not fully finished, but well on its way.



Slingshot crossbows are fascinating weapons. Powerful enough to be lethal (>60 ft-lbs), easy to make and very accurate.

However, all of my power sling-x-bows were pretty long. That is, until now!

I built a bullpup crossbow, with rollers that extend the draw. This has a stirrup and can therefore be cocked with both hands, allowing very strong bands.

Here you see it in comparison with an earlier model of mine:



In this video



you see it shooting triple TB gold bands per side, the maximum I can draw on a conventional slingshot. But the photos already show it with six layers per side, it shoots a 20 mm steel ball with more than 230 fps - well in the 60 ft-lbs realm commonly stated as "lethal".

I will do some more sanding, add a front handle and a scope, plus a nice paint job.

Will make a how-to video (tutorial) for next week! Stay tuned.

Jörg

Hey Jorg: (crazy American computer doesn't have the umlaut key).

Welcome to the site. I have been able to look at a couple of your videos and I have to say. Great Work. You ahve inspired me to try my hand at some crazy slingshots.



Keep up the good work, and the great videos

I followed Jörg over here from the Slingshot Channel. I personally get around the lack of an umlaut key by cutting and pasting the ö.

Welcome aboard Jorg,I love all your slingshot's as you really have taken these weapon's to another level.Simply amazing with brilliant video footage.I love the gatlin slingshot and all the other's i have seen and your traditional hand held slingshot's are so neat and beautifully crafted as they are powerful.Very inspiring stuff i just love it,that bullpup version is AWESOME and i cannot wait to see her party with the uprated band's,very cool interesting weaponry there with brilliant trigger mechanism design's with sound woodwork,wow you are one bad boy,so glad you are on here.

Jorg, excellent to have you here! I have watched your clips on you tube for a while now. I just loved watching you shred up the leg of New Zealand lamb. I look foward to when you post a super accurate "stone bow" delivering 120 footpounds plus.

Again, nice work!

James

Jorg to me you are quite simply THE SLINGSHOT GOD period,no kidding.I want to make one myself now and i think myself that if you brought out a commercially viable version then there would be a fair few people out there who would love one as they are brilliant fun and shoot very cost effective ammo.Just immagine that BULLPUP VERSION all finished in black or camo now that would be on my Christmas list right at the very top you could even incorporate a winch for ease of very high power use on it and it could shoot bolt's as well,hope i got you thinking on this Jorg as no one else out there has offered a slingshot of this calibre.I also love the German HW 80 air rifle it is so well engineered and designed to me it is the best. I have had these in 177 cal through the sound barrier by tuning it and getting a monster high quality spring made.It sent a pellet clean through a lorry tyre both side's and accurate too the kinetic energy was 29 ft lbs.I now have a .22 and that went up to 32 ft lbs with stroke modification and transfer port mod's and making the piston heavier with two spring's ie one inside the mainspring.

All I can say is two words... DA-amn!
Jorg you da' man!

Jorg to me you are quite simply THE SLINGSHOT GOD

"It's not the Gods who bake the pots" and in that lies my complement.

The few issues shown in the video closely relate to what I asked Joerg on another forum. The modified frame I was discussing with jeep. Since recently I've learned that the band can't be pre-tensioned like the limbs of a bow, it's now obvious that it's very easy for the band/string to slip off the rollers at the end of the power stroke. I believe you've already made your modifications to solve that problem.

The next issue is the cheek rest and scope mount...and the biggest two issues with those is you didn't give yourself much room for the two and the position of the forks would make it hard to draw with most side mounted solutions. However, since you are calling it an "assault" sling-bow, I think it's a must to figure this out.
There is room for an "over the track" rail (most video games have at least one bullpup rifle with front mounted scope ) that will be simple to build and solid to boot...while still allowing you to draw with both hands and not dealing with any swing arms etc.


(Yeh, that's a piece of foam pipe insulation as a cheek rest. )



Looking forward to the updates...I know you don't really copy any design, so will be interesting to see your take on it. Good Luck!

Ivo

Now that is very nice indeed.Ivo that thing look's like nothing else.Love that design and what a compact weapon it is along with being powerful and accurate.

Ivo, great pics, and I am sure your construction works. But there are two issues to consider:

1. The bridge makes it a little harder to draw out the bands.

2. The bridge needs to be higher if you employ my simple "push up" trigger, as the ball flies slightly upwards and may touch the underside of the bridge.

I will try a folddown (swingarm) scope mount instead. That has some accuracy issues due to the unavoidable play (the end position varies slightly), but for the effective range of the weapon, I do not think this matters much.