I know this seems to be a very controversial debate and the reason being shot placement. I am a good enough shot I think I could use the .243 Win very successfully on Eastern Oregon Muleys. I just got my .243 Win and finished breaking in the barrel. My 25/06 barrel is shot out so my new .243 will be going with me this deer season. I understand the 2000fps and 1000lbs energy rule and if I went by that, depending on bullet weights, what type, etc.. the .243 looks like a maximum of a 400 yard deer cartridge. A lot of times my shots will be 450-550 on deer. What bullet would you recomend using? I was thinking of the 95g B-tip, 85g Barnes XLC, or the 90g Swift scirocco. Also, this is the big question, how far do you guys think the .243 Win is capable of taking deer effictively at the cartridges maximum limitation? I know most dont go by the 2000fps and 1000lb rule. Thanks for the help guys.