If you are thinking of using the rifle as a Coyote gun you might want a scope with a little magnification. You might look at something like a Leupy 1.5-5 with a hvy duplex reticle or go out to Gene Sears and buy one of the fantastic low powered Nightforce scopes (talk to BJ for the best price).
If you are mounting really about any optic you can't do better than a Larue mount.
http://stores.homestead.com/Laruetactical/StoreFront.bokLarue stuff is the very best made period. Be forewarned that there stuff is so popular that there can be a signifigant wait for it, Soldiers and Operators come first, but it's worth the wait.
The mount that comes on the M-4 is pretty good. H&H has them for around $725 or so if you want one quick. You might save some shopping around but H&H isn't too far off. Larue has a package deal that's real tempting but I don't know how long you'd have to wait.
On one of my other 556's I have a Comp M2 Aimpoint in a GG&G mount. It's lighter than the M4, cost less but the batteries it uses are the round camera type batteries that cost more and are harder to find than AA's. Still a good site though. H&H has some of these at not too far off prices.
If I were you I'd go down to H&H and talk to Twan. He's a really good guy and a freind of mine. He'll show them all to you. You might also look at the Leupold tactical scope. I think it's a 1.1-4 and is pretty cool on a tactical rifle, Twan has one on one of his AR's. I don't have one myself but have been thinking about one. Sears may or may not have these cheaper than H&H.
Usually H&H keeps a better selection of sites for AR's and 556's in stock. Some of them they have decent if not great prices on but at least you can look at them side by side.
The coolest trijicon IMHO is the one that has the red dot scope piggybacked on top so you get the best of both worlds. It will cost you more than your rifle though!
If you handload I recommend that you find some 69gr Sierra matchkings and load them behind 26.0grs of Varget in commercial cases. This load has shot goot to great in just about every 223 with a 1/9 or quicker twist that I've tried them in (probably a dozen or so!). It's a good solid load to start from.
Good luck with your 556! Tell Twan I said hey and sorry I can't afford the SCAR yet!
.............................DJ
