Hi guys, as far as I am comcerned the best target frame is an old 240 Lt wheelie bin. My family owns a small garbage company and so I can get my hands on ones which have broken handles etc, you can just tape the target to the front of the bin, and shoot away. I also have a smaller 120Lt bin at home which I have filled with sand, have even shot it at 50 meters with a .270 and 130 grain woodleighs, NO exit.
The bin is easy to move from one yardage to the next, and its big enough so that you can have lots of targets on the bin at once so you dont have to change targets all the time.
Just my thoughts
Steve