My First AR Build - beginnings - Complete Lower

Here is the start of my first AR build. A friend is helping advise and build (where applicable). It will be a 16" 5.56x45/.223. The type of upper I will most likely chose is a "mock dissapator" with carbine length gas tube and mid-length rifle sights. The idea is to have a relatively inexpensive hunting rifle/home defense rifle with a high capacity and proven durability using mostly MILSPEC parts. For now I plan to stick with iron sights.

So far I have a GWACS CAV-15 MkII fully populated lower, couple of Magpul 30rd PMAGs, a Gen 2 (with floorplate) and a Gen 3, a BCMGUNFIGHTER Charging Handle Mod 4 and a Magpul BAD lever.

Parts:
30 rd Gen 3 PMAG
30 rd Gen 2 PMAG
Magpul Ranger floor plate (for the Gen 2)
Magpul BAD lever
BCMGUNFIGHTER Mod 4 charging handle
GWACS CAV-15 MkII complete lower (with QD sling mount added)

More on the lower, GWACS Product Description:

Light Weight single piece polymer AR-15 lower receiver. Fully populated CAV15 includes carbine buffer, Carbine buffer spring and complete lower part kit installed. This is a Polymer AR-15 lower with lifetime warranty*. Includes take down pins, MILSPEC trigger group, buffer, and buffer spring installed and tested. A1 Length Integral Stock (5/8" shorter than A2) with sling loop. 13" Length of Pull. Receiver weight (complete) is 1 full pound lighter than a complete aluminum receiver with an A2 stock.

Wider magazine well accepts unmodified, submachine gun magazines in pistol calibers. With caliber conversion upper receivers and magazine blocks, standard AR15 magazines can be used without modifications. As well, any M16 magazine can be used with easier reloading than aluminum receivers.
It has a longer service life, as Nylon6 resists impacts and wear better than aluminum. The integrated buffer tube, pistol grip and fixed stock give this design its strength.

Enough will all that, now the good stuff...