Need some input on selection please.
I'm looking at buying an AR of some sort, I haven't decided if I want an AR-10 or AR-15. This is where I need some help. I don't really know much about guns brand wise, such as who is better then who. I'm in the Army and I've used a colt M4 my entire career. I'm kind of leaning towards the AR-15 just because I know how to shoot it, I know how to zero it, tear it down, fix it, etc. I've also messed around with a Scar and its pretty awesome. One of the special forces guys had one. My budget is $3000. The only must haves I want are either a red dot or acog, fore grip with bi-pod pop out and adjustable stock.
I just need a little bit of help, simply because I don't really know what is good and what isn't all that great. I've never really been in depth into the civilian gun world but I get to play with some bad guns at work. Give me a .50 cal, mark 19, 320 or an m4 and I can tear them down, fix them, shoot them, zero, time em etc. I'm just not familiar with the civilian side of things.