Home Forums Hunting & Shooting AR and Tactical Rifles Need help picking a new AR!

I'm not an AR expert, so I need some help from you guys. I'm looking for a AR I can use for long range shooting (probably a max of 400 yrds), so accuracy is important. I've narrowed my search down to Rock River Arms, but need help on the following:

-Which model should I get, the varmint A4 or varmint EOP? Is the "elevated optical platform" make that big of a difference?
- What length barrel? If I went with a 20" tube how much velocity would be lost?

I'm sure there are more, I'll add to this thread as I think of them.

Thanks!

Not an AR nut myself but I shoot a post ban Armalite 20" flat top upper with a weaver gas block. I have a pair of Burris quick detach rings and with a 40mm objective my scope barely clear the handguards. What I have read is that whatever ring base combo you use should put the center of that scope 1 and1/2 inch above that flattop. Mine is at 1 in. and you really have to get your cheek down on that stock to get a proper sight picture. With the elevated platform you could use lower rings as long as the objective clears the platform. Never chrono'd a 24" but I shoot a 20" as we have found about 200fps difference between 16" and 20" with the 69gr. Noslers we shoot. It becomes an issue of how much weight you want to drag around and how you deploy that rifle.