I've used PVC bows for a long time as "toys". We made them when I was a kid for bow-fishing, then I've taught my younger cousins over the years how to make them. I actually just built a pair of them for one of my nephews to keep on his boat so he'll always have them, but won't be as conspicuous as keeping bows on board. As a "speed freak" and an engineer, I've tried and explored a few different methods of construction to get them to be suitable and practical options, but really, they just aren't there.
1) They break over time - not much time either.
2) Getting to 50# draw weight is actually harder than you'd think. The problem is that you can't double sleeve the PVC inside itself with a small enough diameter to be practical and still have room for enough fiberglass rods to make it strong enough. A 50# PVC bow that will STAY above 50#'s requires a large enough diameter that it's ungainly in hand.
3) They're incredibly hard to shoot accurately. The round tube design and the irregularly bundled fiberglass cores lends itself to twisting as you draw, as compared to a flat limbed bow that resists torque much better. This means a very different
4) They tend to fatigue quite quickly, such that what started as a 50# bow is only a 35# bow within not much time, and then of course, they break shortly thereafter.
5) The quality of construction is everything. If you're involving electrical tape or duct tape - really tape of any kind, you're doing it wrong.
6) Parachute cord is NOT bowstring, and should never be used as such. It's about the slowest bowstring alternative possible.
7) There's a reason that REAL bows have cuts in the riser. Part of why PVC bows are hard to shoot is because they inevitably have a a big offset from centershot. This contributes to the torque, but also to poor arrow flight.
So.... With all of that said, I'm not very compelled to spend time building them anymore when $50 will buy a used recurve, or $100 will buy a new one.
Guys can kill a deer with a spear from 20yrds, and I'm confident that plenty of deer have been killed with rocks, but for my time and money, and
considering my respect for the game that I am hunting I wouldn't ever take a PVC bow out after deer.
