We are not using the targets properly. Correctly done, the outside ring represents the perimeter of the kill zone. I wanted to give the people who ONLY have access to a 10 yard range a chance to shoot at a decent target so I opted to use the middle ring.
Use the middle ring to figure TF. Proper target use will probably be one of the changes made to the next shoot, it will depend on how this one goes. A 15 difficulty @ 15 yards is a 30 TF because we only use half of the 1" KZ, 15yards/.5"=30. Your 10yard target/.34"="29.411 TF", 30 basically.