Ball shooting Crossbows worth the bother

First topic message reminder :

Been looking at ball shooting crossbows to see if they have the potential for accuracy compared to using a bolt/arrow. Also the life of the limbs/ prod firing a light ball, lighter than a bolt/arrow that it was designed for. Seen some reasonably priced cheap end ball/arrow shooting crossbows just to give it a go and to see if i could make one, but not worth the effort if these are just a fad or gimmick. what do you guys think and has anyone used or own one, can't seem to see any reviews on the web. https://www.surplusstore.co.uk/armex-hawk-of-the-forest-ii-recurve-crossbow.html
See here as an example. Thought shooting a ball would benefit in not loosing arrows or bolts. Also would lead be better than steel ball especially bearing in mind the ricochet factor.

I was very surprised how hard it hits with 44 cal lead balls with the 50ib prod. I tried 9mm lead balls and they seemed to fly much harder and flatter out to about 100 meters without a proper guide which i am making for a dedicated size 8 or 9mm.

What setup are you shooting with? Is it a slot with a shuttle to shoot the ball?

50 pounds is good enough should you have a good bow. I recently made a bullet crossbow with a 60 pound prod and it works just fine.

I just wanted to experiment and make a small compact crossbow, so i robbed a prod and string from a cheap chinese crossbow pistol with a metal prod which is a pressed steel type. The whole construction going the modern looking way was made from 20mm square metal tubing brazed together to form a stock with the tiller made from 16mm thick tubing slotted for the bow string to slide up and down which fits perfectly into the 20mm stock held in with a butterfly screw for quick take down. The prod had to be canted at an angle to allow the string to sit centre of the tiller slot. The release mechanism is a simple quick release catch clamp or toggle clamp used to hold down work pieces. I used this as a release for a slingshot rifle i made, its very strong and i have added a return spring on it for better release and to hold the clamp in place when the bow is cocked, works perfect. The whole look of the ball shooting crossbow is very simplistic and modern in looks. Al i have to do is make a insert for the middle of the 16mm tube so a matched ball can run true down the middle. At the moment it shoots quite straight and narrow with a lose fit down the square tube but would be much improved with a new made liner.The sights  which are adjustable are constructed from the steel tubing by cutting shaping and forming. One i have perfected it by sorting the ball to fit liner i will blast clean it, phosphate the steel work and black wrinkle paint the steel frame work.

Sounds really nifty, would love to hear more about it as you make it, keep me updated. The 16mm tube serves as the barrel, right?

Yes it serves as a barrel which is 12.5mm id. It can fire bolts which i have made without fletchers and made a jig which cuts out 4 evenly spaced flutes at the back of the bolt about 3 inches as a fletchless bolt, you can have three flutes if you want made from 12mm dowel with a flat head made from studding connectors which are smooth rather than nut shape about a inch long just machine the dowel down so the connector thread takes a bite into the shaft to screw on. The barrel tube when its made will accept a metal liner which is slotted and bored at 8.2mm to take ball or it could take a 8mm fletcht bolt.

Regarding "lead pollution" with lead projectiles the problem is grossly exaggerated and is really only applicable to fine lead shot that falls in shallow water where waterfowl can find it easily. Ducks ingest the shot believing it is shiny stones then hold it in their gizzard and grind it together with real stones to process foods such as seeds and grains that are processed by the gizzard prior to final digestion.

Not really an issue unless there are incredible amounts of fine shot being dropped into a clear body of water frequented by ducks and geese. Lobbing individual lead balls around on dry land has no effect on anything unless you have small children running around eating them.

Bit of a update. I decided to use a round plastic carrier to push the ball out that fits in the square of the tube body. The carrier has two holes in it at right angle to each other, one hole at the back to engage with the trigger and the other hole for the string, at the front i bored a slight hole about 9mm x 6 mm deep for a 8mm lead or any projectile .44 or 9mm to sit. When the crossbow is cocked the carrier sits in front of a curved wire spring that holds any ball size in the carrier, the curve of the spring rides up when cocking and ride up out the way when firing. Upon firing the inertia hold the ball centre in the carrier, so accuracy is consistent, no need for the projectile to rely on the tubing body of the crossbow only the carrier. Crossbow fires very well very pleased with results, the balls need to be made consistent  ie all same size and weight for accuracy. Shame i cant down load pictures quite simple to make.

Gezzer , on this site relates a bad experiecne with the ball crossbow. His was of original  design, and some how it back fired. From what I remember it was kinda common . The originals all shot a dubble string and some how would hold the ball and fire it out on the rebound of the string. A little un nerving to say the least. There were people selling these ball carriers  on here and they fit on regular crossbows .Worked kinda like what has been talked about.

I think that anyone interested in building a bullet crossbow would be well served to read Richard Middleton's "Practical Guide to Man-Powered Weapons and Ammunition." (It used to be called Man-Powered Bullets, but I guess that was too scary.) He covers most of the devices one might think of to launch a lead ball without gunpowder, focusing mainly on compressed air, but does cover vertical bows and crossbows. The science is laid out in a way that even I can grasp, and it is also an amusing read as un-self consciously makes fun of his pursuit.

I've had a compact ball tosser on the drawing board for a while now, languishing because I keep tacking new-to-me technology on it. Who knows what ideas will make it into the final build, but right now it is a slotted barrel design launching 5/8" ball bearings, powered by a compound bow system with oversize cams and short, rigid limbs using torsion springs. I have a couple of ideas for forcing the ball to roll against the top of the barrel to provide a spin like a backwards-rolling wheel to flatten the trajectory, and am also excited to steal a lever-cocking design from JoergS.
Anyway, good luck with your endeavors!
Gnome