I have had and done a lot of shooting with almost every caliber rifle around up to 416 Rem Mag. I shot 500 meter steel silhouettes for about ten years. Magnum rifles were not allowed in our silhouette shooting. I have had some magnum rifles that shot well and that I could shoot well. All of this said, If my life depended on a long range shot it would be with my 6.5x55 swedish mauser. I can shoot long range best with that rifle. As long as you know the trajectory of your rifle and most importantly have confidence in it, you do not need a magum rifle to shoot long range. The best example of this would be the documented long range shots made by the old 45-70 with black powder. You cant get much further from a magnum than that. 90 percent of the silhouette shooters including me shot 308 rifles with 190 grain BTHP bullets. The bullet is what count more that what shoots it.