I know of a few places around Hattiesburg that are used as public ranges and have been for quite some time, but all of them are a bit sketchy to me. One is in the DeSoto or on the edge of the DeSoto south of Hattiesburg, one is off 98 headed toward Mobile, and the closest one to the area you mentioned is off Hwy 589 near Epley between Sumrall and 98. PM me if you want directions or more info. It is nothing more than a gravel/dirt pit like area on what I was told is 16th section land. There is a lot of brass/hulls on the ground, so someone has definitely used it for shooting, and I was told about it by a guy that occasionally uses it. I haven't shot there though and would want to look into it further before going to shoot.