I had posted this erroneously on someone else build. I have used all manner of weapons my entire adult life. While I miss the ability to fire full auto - now that it's my limited dollars, I won't miss it all that much. My lower/upper receivers/BCG: http://shop.si-defense.com/product_p/si ar-15 lwr-al.htm SI Defense AR-15 Billet A3 Upper Receiver, Stripped Barrel: (although I'm a little concerned with the maker, but we'll see how she fires in the spring) AR 15 Match H-Bar Rifle Barrel - 16" No fixed front sight. I will be attaching folding sights, just not sure which manufacturer quite yet. As this is a carbine length weapon, I stayed with the standard trigger from RRA. If I decide to build a different upper (possibly 6.5 or 6.8, or maybe just a 20" stainless barrel for range/match shooting), I'll be buying a much more expensive drop in 2 stage trigger. I hear good things about RRA's NMA 2-stage triggers as well as Timney's. Pricey that last one...... Handguards. The last M4 I carried had Vltor CASV-EL - partly because of the ability to mount an M203. I'm accustomed to the feel of these handguards, but am open to something comparable if you have any suggestion. I frankly loved the Vltor Modstocks and will be going with one of them. I'm not doing high risk entries anymore, so I may skip the Tango down foregrip.. I'm looking at a flash suppressor or compensator, but honestly, I've fired so many rounds down a barrel of either an M16 or M4, I don't think the rise is all that big a deal. Any thoughts on this and a preference? I've already got a good cleaning kit from Otis. Ammo is another area where I could use some help (both for plinking and more serious shooting) Optics - as this is a carbine, it would probably be smart to go with a red dot. I've been drooling on sights like Planet Optics now for about 2 months.