I posted this in the traditional forum since that is what I use to kill this hog with, but thought some of you might have experienced some thing similar since I was using carbon shafts. Heres the story:

I shot a hog the other day with my old recurve. I was in a tree and the hog was about 20 yards from me and 10 feet below. I shot him with a quartering away shot. The arrow went right where i aimed, which was high and back a little. I was aiming so the arrow would exit low and behind the opposite shoulder. From my angle, and the shot placement, it should have. The pig droped right in its tracks. It squirmed a little then expired. When I recovered the animal, I pulled out the arrow and to my surprise the broad head had been snaped off at the base. When I looked on the back side of the pig, there was no exit wound. I thought I hit the inside shoulder blade, thats what must have cause the problem. Not unusuall with a thick hog. When I cleaned the animal, I looked to see if the broad head was in the opposite shoulder, or in the shield, it was not. I then searched the thorasic cavity and found it lodged deep in the spin. Looked like I had shot the hog while it was laying on its back. I can not figure out how the arrow bent and went straight up. Mind you, the arrows course was a sharp angle down. How it turned and went straight up is beyond me. I switched to beman 400 carbons last year, which would explain how the arrow bent with out breaking, but does not explain why it bent upward in the first place. This has got me stumped. I have never seen an arrow do this.