I'm loading up 500 rds. of 223 FMJ that shoots about 2 in. or so at 100 yards. That good enough? If not I'm not real sure what else I could do and be ready by Saturday. Also not real sure I have the right kind of sling and don't have any kind of mat. I figured a heavy blanket, maybe yoga mat type thing might work. Never done anything like this so not real sure what to expect.