I have a friend who is really wanting my old Rem 700 BDL in .280 Rem. He wants to trade me his Win 70 (Shadow?) in .300 WSM for it. I'm not willing to trade straight across I don't think but am not sure what the value of my or his rifle is. Is there a good "bluebook" for used rifles. I also have a B&C Synthetic for the .280. Since he is a friend I don't want to cheat him, but don't want to skin myself either. I have no emotional attachment to my .280, and since I own a 7-08 it is sort of ignored anymore. I also don't own a bolt action .30 cal of any kind. Any ideas.