I unlike the others feel that with the correct load and bullet, this rifle is very capable to 500yrds with a 165 to 180 class bullet. The ballistics are there, but shot placement is important. The best load that you could use IMHO is the 178 A-max or the 175 SMK, Berger. The A-max by Hornady would be the best option for expansion next to the Berger. You want to be able to push these bullets for that distance somewhere between 2550 and 2650. With that said the 168 A-max would also be a good option.
Let me pick your head a little. Are you sold on .308? Were you looking more at the .223? I'm going to throw a couple of other options at you. 6mm/.243 may be a good option as well. You could find this in most sporter rifles. A tight twist 22-250 would be an option as well as long as you use heavy bullets.
Here is one that maybe you should consider. You can look at several different models and variations but I forget about this caliber and it may just be the ticket. The 7mm-08 with a 140 or heavier bullet just might be the ticket if you are not wanting a magnum. The reason that I chose this one, is the 162grn A-Max or the 168 Berger. You can push these bullets in the 2700fps range and the ballistics on these bullets are phenomenal. They are both high BC bullets providing you with the down range energy you want.
Savage Centerfire Hunting Rifle 16FHSS
As far as magnums are concerned then any of the WSM's or Long action magnums will do it for ya. Just some thoughts.
Sorry to add to the confusion, but just offering suggestions. Again I am a firm believer in the .308 being capable of what you are asking of it.
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