Earlier this year, I discussed the possibility of using a crossbow to launch golf balls. Well, I have constructed one using one of those cheap "rifle" crossbows for donor parts.
Its very simply constructed from a piece of 2" aluminium box section and I didnt spend a lot of time on fine finishing since it is a development project and will probably require modification. As expected, its not very powerful, parly due to the low draw weight, 120 pounds and the fact that the balls are fairly heavy compared to bolts. Accuracy is acceptable at 20 meters but I havent tried to shoot further yet. At the moment the balls are a loose fit in the "barrel" but I will add shims which should improve accuracy. Since these photos were taken I have added a foregrip and made the stock detachable.
It looks like a bit of a beast but is no more awkward to handle than an ordinary crossbow. It reminds me of a grenade launcher somehow!