500 yard beginner rig?
Savage 10fp in 308, or precision carbine, high price of $800 (estimate) add another $800 bushnell 4200 6-24x50 tactical scope, add another $100 for good burris signature zee rings...go nuts and have fun! That rig would teach you how good YOU can shoot.
Mine loves 168gr hornady bullets and varget powder....500 meters is easy....I set up 10inch metal plates and let my kids smack them over one by one.
If by chance you live in Alberta I'd certainly be up to teaching how to shoot that far. I'm by no means an expert, but I can teach the basics required to get oyu accurately 500m out. 5-6" groups (10 shot) out that far are certainly possible with 308.