I used cardboard stacked 2 feet high by 13 inches deep. By using a 2x6 on top and bottom ,I would compress thecardboard by using threadedroads top and bottom . Stopped anything but was really hard to get arrows out of . Alsoo was so hard to get arrows out, my broadheads would pull the inserts out of my arrow.[:@]And target was really , really heavy.
If you can keep your target inside get a big cardbord box and fill it up with old rags and clothes. Its cheap and should work with fieldpoints
Good luck.