Re: AR-15 help me decide
I'll save you a lot of time and money. Forget building it yourself unless you plan on building a lot of them. I build my own, but I can't get what I want, I'm way too picky and the rifles I build would cost me double to buy them that way even if I could.
If you know someone that already has all the shit, go for it I guess, but make sure they know what they are doing and actually have ALL the shit, including the blocks and even the roll pin starting punches. Know all the tricks for laying out tape and such to keep from marring your parts.
Otherwise, do this: LMT makes the Defender 2000. It is a VERY well built lower and it comes with their superb SOPMOD stock. They are very expensive stocks, the only economical way of getting one is to buy the lower. I have two of these lowers myself. I eventually put a Geissele trigger in, but you don't have to right away --or ever. They come with a single stage for around $425, around $500 for their 2 stage. The one stage is fine, I'd use that and replace it with a Geissele if anything, later on.
Then get the LMT upper. They sell an M4 16" or 14.5"; get the 16", especially for your first one. The barrels are well made, chrome lined. They come with the double lined M4 handguards. They are $450. Then you'll need a bolt carrier/bolt assy. $100. So now $(425+450+100)=$975. Under $1000, and you'll have an all mil spec, "military grade" basic M4 rifle. On top of this, it will be an actual LMT rifle, not a parts gun. Go look up and see how much LMT charges for an already built M4.
Then for sights, you can use the excellent LMT iron sight, it is just the regular A2 sight without the carry handle, or even better, an EoTech. That thing is without a doubt the fastest close range optic on Earth. Good to just under 300m like the Aimpoint too. You could get the EoTech first, then get a backup flip sight. I like the KAC 600m regular or micro. The micro is just as good for a lot less; basically the same thing really.
Later you can add the FF rail if you like. I'm a big fan of KAC, I have several of their rails and the URX2 or URX3 is probably the best out there right now, definitely the most versatile. Even their non-FF rail isn't bad, the top locks down tight and doesn't move. Larue also makes a good looking FF rail, a lot like the KAC actually. Heard good about it. Troy is supposed to make a good one too, but I only use the KAC stuff anymore. Costly, but it has never let me down. Worth saving up and doing it right the one time, trust me on this one.
Stick with DI. It was made for it, it works, it keeps it lighter and parts move with the force applied in the correct locations so parts wear the right way and don't warp or break. The small, light DI gas tube with no moving parts is also part of what makes the AR so accurate. It costs a lot less too. Don't mess with it! If you get a gas piston, be prepared to shell out for a well built, factory rifle from someone like POF or maybe an SCAR or some of the others. Something designed or redesigned ground up to use it.
So bottom line is you can try and build a better wheel, but you'll find that is hard on a budget. I'd strongly suggest you didn't build your first AR. You really have no reason to, especially since you just want an M4, and it will cost you more this first time just for the gear, and you are already on a budget. If you get the LMT upper and LMT lower, you can get a GREAT M4 rifle, all milspec, all built right (and then you can see how "built right" looks and feels).
In a few months, you can have it tricked out with the FF rail and EoTech and be golden.
Here is my rifle, it is exactly what I described but it has a 14.5" bbl. and a blind pinned AAC Brakeout and Geissele 3GSD trigger. But the basic rifle underneath is the $975 LMT M4 special. I built some of my others ground up, but not unless I have to. Just start with a good rifle and add the stuff you need later. Good luck.
