These pictures are from a few months ago.
(the suppressor looks a little canted because it is. Still waiting on my 7.62 can. I put my 5.56 can on just to see how it will look)
I already assembled the AR15 stripped lower a while back so I don't have pics but I can figure something out if someone would like to see the process.
The Lithium grease is applied to the upper receiver threads so the barrel nut will not cease after a few hundred rounds. This will allow you to remove the barrel nut and barrel if you want to later in the future.
Slide the barrel onto the AR upper receiver. There is a small notch in the top of the receiver and a small peg on the barrel so aligning the two is impossible to screw up. Slide the barrel nut over the barrel and hand tighten the Barrel nut onto the upper receiver.
Then use a AR15 Armorer’s Wrench
like the one in the picture to tighten the barrel nut.
Next we will install the gas tube and gas block.
Insert the gas tube through the hole or slot in the barrel nut into the AR receiver from the front side of the weapon. It should slide without very much resistance. I used a little bit of motor oil on some of these parts to help with the install. If the gas tube doesn't slide in very easily then the hole in the barrel nut probably isn't perfectly aligned. Tighten or loosen the nut slightly and try again until it slides in.
Next slide on the gas block onto the barrel and then into the gas tube. There is a small pin that will have to be punched into the top side of the gas block locking the tube and block together. Make sure then hole in the barrel and the hole in the gas block line up as best you can. On this model of gas block to set screw in the bottom of the gas block are tightened to ensure the gas block doesn't move.
Next I installed my quad rail. Each quad rail / hand guard is different so refer to the instructions that came with what you bought.
And that’s basically it.
two other AR15s I built. Both are 5.56 guns.