Unmonitored city maintained range, very few rules other than obey cease fire and don't shoot others/yourself. Why 20? Because normally he starts at 25 yards with his subcompact and hits 99 times out of 100. So 20 is actually, for him, very close. As for shooting steel, if you shoot close, make very sure it is smooth, ( dimples can cause uncontrollable bouncback), and angled well down.