[Spartan359]

HAHA you used a hole saw to cut a 4'' hole in 3/8's mild steel!! Man I bet that took about an hour or two. Why didn't you use your acetylene torch to cut the hole and just grind away the sides? You did an outstanding job regardless. Looks awesome. One tip you can do with that steel is to take and heat the center of mass/head ringer with your torch and dip it in oil to harden it. It also would help if you heated the areas that you know rounds will hit. Like on the sides of the ringers. Heat it up and dip it in oil a couple of times and you should be good to go. Just don't use and AP rounds or FMJ and you should be ok.