Try this. collect as many plastig bags to fill a small room and stuff them into a burlap bag or large box. Either sew up the bag with twine or wrap the box in tape. You can also layer in old towels for more stopping power. Note the tape from the box method will leave a residue on your arrows.
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Don't believe everything you think.
Hey the best target I've built is a burlap sack filled with any kind of plastic. Wether it be walmart bags, garbage bags or even old poly. But you take the bags stuff it in the sack and I mean stuff it good then cut a piece of plywood for the opening of the sack. After you put the plywood in take a heavy duty stapler and staple the burlap to the plywood. After that is done turn it upside down on the plywood and tada a target that will last for years. The target I built is going on 12 years now. Good luck and shoot strait
I make mine out of burlap bags stuffed with plastic as well. The ones that you get at Peavy mart are better quality and much cheaper than the ones you buy at archery shops with animals printed on them. I buy about ten of them and then fill a couple with plastic bags that I steal from the recycle depot and stitch them closed with wire. When they start getting shot out I just slide another burlap bag over top and stuff in a few more plastic bags, way easyer than starting over.
One thing I often overlook that you need to do is build a frame to suspend it from. I used to lean mine against my shed but now my shed has lots of holes in it from arrows poking through the target. Its harder on your arrows too.
I've made some using a plywood frame, nail an old piece of carpet on one side, then stuff it full of old rags, blankets etc. Nail a top piece of carpet on it and away you go. Mine work great!