I agree with dvdegeorge, 7mm08 is a good kid round. There was a 12 year old girl hunting with us last year and she was shooting my boss' s 7mm08 with no problem. If you have to have 243 or 25-06, I' d go for the 25-06. I' ve seen whitetails take four rounds in the vitals and keep right on going. My mom used to shoot 243, the last season she used it she lost 2 deer. First one she hit 4 times in the vitals. I trailed him for 1.5 miles before I lost the trail. The second she hit and he just kept on grazing like nothing happened. Since it was getting dark we gave up and went home. Came back the next morning and found him about 50 yards from were we' d last seen him grazing. She moved up to 7mm the next year. Just my 2 cents worth.