um 500+ yards.
SPR Varmint Target type build. Prolly gonna want a rifle setup, with rifle gas and 18+ inch barrel, stainless barrel.
For $2g, I'd start looking at some glass/optics a 4x prolly isn't give you want you need at those distances. Also start looking into barrels, as these two will probably be the most important factors in your success.
Hate to say it but you are looking at the high quality glass, you can and may blow your whole budge just on a scope.
You will definately want a 1x7 twist or 1x8, so you can use the longer/larger bullets, and handload as most store bought ammo probably isn't gonna cut it.
There are some with AR15s that can get out to 1000+ yards, but at those ranges your budget will definately limit you, even if you buy used components.
One thing that you might want to consider is build a med range plinker that will easily go 300-400. and then if you like the AR platform, build an precision upper with good glass on it later. It will only take your 5 seconds to swap out uppers. Consider this: $700 for a budget 16" AR, shoot the snot out of it. Then if you want to go longer, get a new trigger, build a new upper, get some nice glass later. 500+ yard can be done with a 16" ar, but its not optimal, you'll want a longer barrel for more velocity.
Assumption is the mother of all ****ups.
Know what you know, Know what you don't know. -Paul Pedzolt
"Jack of all trades, master of none, though oftentimes better than master of one" -Mynshul
Last edited by AgentTikki; 12-13-2011 at 05:50 PM.