I would like to know the biggest differances between the two cartridges.First,I already know the 300 is a bigger bullet and a mag.That is not the kind of differances i'm talking about.I'm talking about knockdown power,effective killing power out to longer distances,and overall cost,reliability,and practicality of these cartridges for deer and larger sized game hunting.The reason I'm wanting to know is because I have found the rifle I want,but it's in .300 win. mag and I think it's a little too much gun for what I need.The gun shop I found this rifle at said they could order the .270,but it would be about a month before it got here(and I want it NOW).I live in TN and 300 to 400 yard shots are probably the longest shots I will encounter in the areas that I hunt.I have hunted out west a few times and I do plan on going back,but for the most part I will only be hunting in TN.Thanks in advance for everyones input!!