If you're shooting a .22 in competition, it better say so on your registration card or if you switch from a 6mm to a .22 during competition, you are required to tell the range officer when you switch who'll then tell the scorer. If you switch to a .22 from a 6mm and don't tell the range officer, it's grounds for disqualification. If you switch from a .22 to a 6mm during competition, you're only hurting yourself. Any scorer that's any good can tell a .22 bullet hole from a 6mm. A lot of times the scorer will go through the targets and mark .22 on the targets that are shooting .22's before he scores them just to make sure that they aren't miss-measured. As with anything that involves competition, there are people who will cheat in order to win. If they do, what have they won. There's not much money in benchrest and the wooden plaques you win are probably worth $10 if that. There have been lots of range records below world records before the club went to moving backers. It's strange how group sizes increased when they went to moving backers and also the guys who were winning before somehow lose interest and quit.