Lightest/smallest AR build

I've never built an AR so bear with me.
Throw some ideas at me as far as parts and brands for putting together the lightest and smallest AR I could, without getting tax stamp or doing a pistol, that you would trust your life with. For about a grand not including optics.
Go.

I recently fondled the bcm with kmr handgaurd. It was pretty nice and light

OR
I already have a Troy Conqueror. It's pretty light but too long (18 inch barrel). I could just change barrel (and hand guard) to 14.5 with pinned brake right?

I'll check that out.

Pistol lower with shockwave blade or Sig brace, pistol upper with short aluminum handguard, iron sights. I've got a similar setup with a red dot on top instead of irons, and based on my crappy bathroom scale, it's like 7 pounds.

There are a couple things to consider here that will really save you weight without costing too much money:
1. Choose the lightest barrel profile you can find. Pencil barrels, although they're not great for long strings of fire, they'll save you the most weight for the lowest cost.
2. Choose your handguard wisely. Don't go full cheese grater quad rail- do something like the Midwest Industries Lightweight series. If you go with a short rail too, it'll save a lot of weight. My 7 inch MI Gen 2 SS weighs like 7 oz.
3. Be happy with iron sights. Adding optics will add a lot of weight, so irons are the way to go here. But some people aren't comfortable with making shots at distance with irons, so this may not be a good option for you. If you want an optic but want to save weight, you could do something like a 3x or 4x prism scope. They usually weigh about a pound instead of the 2lbs that a 1-4 with mount will weigh.
4. I guess you could go with a poly lower, but I haven't seen any that I really liked. They seem to all be out of spec or just poorly finished. TN Arms Co seems to have a good reputation, however, so you could try one of theirs.

Sure, you could pay a lot of money for something like the F3 skeletonized upper and lower, but an AR under 7 lbs is pretty awesome to me. If you buy these parts from PSA, you could put your lightweight rifle together for less than $750.

I'm not a law breaker, but who would really care if you put an 8 inch upper on your lower?
I'm sure some may find this appalling, but who realm cares. That pistol buttstock appears to be just a way around the law.

I'm thinking of getting a 8 inch upper for my lower and keep it in my home for "protection".

But does anyone really care, I talked to many cop friends who dont mind as long as someone is legit with no crim history, or not a gang member and don't try to open carry it.

The feds care. Probability of getting caught and convicted is probably slim but it ain't worth it to me.

Some makes will have a light profile that will shave a little. Stay with forged instead of billet will also

x1000

Wouldn't be a good idea for me.

14.5 inch pencil weight barrel with a pinned brake and a carbon handguard would be a good starting point. I'm sure a lot of weight could be cut in the stock but not sure of any specifics.

Supposedly my factory gun is 6.5 pounds but it doesn't feel like it. My biggest mistake was going with an 18 inch barrel I think.
http://troydefense.com/portfolio/troy-conqueror-3-gun/

https://shop.bravocompanymfg.com/BCM-REC...-750-790-lw.htm

Probably something like this would be almost as light as you can get for a quality product and decent price. With at little micro optic it should be much lighter

Good way to never get to own a gun again....after you get out of jail that is.

A tax stamp is another 200 bucks, just figure it into your build. A Form 1 is really not that difficult to do and a basic trust isn't very expensive.

You know where I can handle one of these in person?

Its the law. Dont be cheap and dont make the rest of us look bad. Your "cop friends" dont work for the federal govt.

these guys: http://2a-arms.com/collections/all build some unbelievably light stuff.

Either the whole guns or pieces and parts. Be an excellent way to start.