Building an upper

[cgseanp1]

I've built AR lowers, but never an upper. It doesn't seem as straight forward as a lower considering you just need the lower, LPK, and a stock..

What parts are needed to build a complete upper receiver?

If I were to buy a barrel and bolt, what else would I need?

Thanks

[stphnman20]

Building an AR upper is much easier and simpler then building the lower.

Upper receiver
Barrel
BCG
Forend

[cgseanp1]

Building an AR upper is much easier and simpler then building the lower.

Upper receiver
Barrel
BCG
Forend

Thanks.. I'm confused on the BCG.. I know what it is, but not what parts make it.. If I already had the bolt, what else would I need to make that? I'm searching around online but can't figure it out.

[stphnman20]

If you have the bolt, then all you need is the carrier, firing pin and cam. But If I were you, I'd get a brand new BCG from BCM.

[cgseanp1]

If you have the bolt, then all you need is the carrier, firing pin and cam. But If I were you, I'd get a brand new BCG from BCM.

This is for a 5.45 upper.. is that the same BCG? That's something else I'm confused about.

[1911su16b870]

Upper assy difficulty is making sure you have gas block/barrel port alignment and torquing your barrel to the upper receiver. Otherwise no problem.

[Etihtsarom]

Could you elaborate on that part?

[Noobert]

Here you go folks

http://www.brownells.com/.aspx/lid=11004/guntechdetail/How_to_Build_An_AR-15_Video