My first target was two layers of pile carpet tied over two bales of straw stacked one on top of the other. I think I paid $2.50 each for the straw and picked up the carpet for free. It lasteda good long time. I have a book that was printed in the early fifties by Popular Mechanics that has instructions for a cardboard field target. It says you cut the cardboard into strips 12-16" wide then roll it as tightly as possible. They used rope with a loop tied in one end to compress the target, but the ratchet strap idea would be even better. Use duct tape to attach each new piece of cardboard then duct tape the outside when you have the roll compressed. The nicest thing about the design was, you will wear out the center first. When it wears out you cut out the center then roll a new center and fit it in.