This question is for those guys that have done it already. Thinking of building an AR10 and would like to know, what parts are not standard? I know the bolt and barrel will be different, but what else? Can I use a standard lower completion kit? or will all my parts have to come from Armalite? Thanks!

If you go to the following link

http://www.armalite.com/sales/catalog/components/223lowers.htm

it will show you a list of .223 lower parts and as it says *indicates parts that interchange with AR-10

If you go to the .308 lower parts page

http://www.armalite.com/sales/catalog/components/308lowers.htm

it will show you the AR10 parts and *indicates parts usable on the SR-25

The part numbers on interchangeable parts also match - Armalite does it right on parts, kits, and technotes ;)

Armalite's tech notes 5 and 6 in their library (Armalite.com) talks about a lot of the parts.  Most everything is special to the 10.