The 9mm AR is one of my favorite AR variant.
I build mine on 10.5" RRA upper and Stripped stag lower.
ETA - I also swapped in my 9mm carrier / 9mm hammer combo for ramped carrier and M16 hammer - easier on the hammer pin.
As far as mag go I'm running
2x 10round RRA (Pro-Mag) Plastic
2x 5/20 C-Products
6x 5/32 Steel Colt Pre Ban Mag with Steel Followers (Very pricey)
Here an old pic of mine.
I build mine on 10.5" RRA upper and Stripped stag lower.
ETA - I also swapped in my 9mm carrier / 9mm hammer combo for ramped carrier and M16 hammer - easier on the hammer pin.
As far as mag go I'm running
2x 10round RRA (Pro-Mag) Plastic
2x 5/20 C-Products
6x 5/32 Steel Colt Pre Ban Mag with Steel Followers (Very pricey)
Here an old pic of mine.




















































