Why would you feel the .243 would be too small? The little .243 has downed TONS of whitetail all over the country. With today's bullet technology, the .243 shines as an exemplary cartridge for whitetail. It's ALMOST as good as the 7mm-08 (not a legal cartridge in Indiana) and more than acceptable. If it is literal "rifle size" that concerns you, they aren't just fitted to junior stocks. Many full size adult rifles on the market in .243 caliber. I started all my kids out with .243's in PA and TN and my youngest daughter still practices out to 600 yards with hers. Sometimes further. The kid (she's in her 20's but still my baby so "kid" it is
) can shoot!