I'm WAY too old to climb trees, because I'm too old to fall out of trees. When I read PVC blasters, the first thing I thought of was potato guns. Instead of compressed air, you spray something flammable like hair spray in it and spark it off with the working parts of a piezo barbecue lighter, or other, dumber means. If I'm right, pumping one up with an air compressor seems akin to using smokeless powder in a black powder gun. Mmm, no thanks.
I used to use a long chain shackle, a 4"x8" dee, on the end of a tow rope or strap to lasso branches on the trees hanging over my back yard, and pull down on them until they broke off. Luckily, I didn't hit my myself in the head and end up in the ER. A sock full of sand would hurt a lot less than a heavy-duty shackle you could tow a tractor with. It has a 3/4" diameter cross pin with a hitch pin clip on it, and I have an extra drawbar with no trailer ball in the 2" receiver on the back of my Yukon. In the past I've used this setup to pull people out of the snow with my truck, and I usually leave that drawbar in place all winter, then swap it out the first time I pull my trailer up north in the spring. It's kind of like the shackle in this picture, but with the hitch pin shown at the right, instead of a screw in pin. The pin was a lot longer than it need to be, so I cut it down to 5 1/2", ground a taper on the end, and re-drilled it, so the hitch clip is right next to the shackle when the pin is all the way in.