I need some input on what would be a good starter rifle for my son. He has successfully passed his hunter's safety course and has been shooting with me on numerous occasions. The place we will hunt is privately owned in north central oklahoma. Most hunting will be done from several different stands we have placed on the 100+ acre place. I have taken many deer off there over the past 5+ years. Most of my shots were 100 yards or less although there are plenty of places to shoot 200 yards. I've never found it necessary to take one of those shots as the deer are plentiful. What caliber/mfg/model can you recommend? He is 9 years old and average size.