Roc Doc
2A SNBI
OT, for a first timer, I say buy a M&P or other such fully built rifle. If you want to trick it out, you can substitute parts or build a whole new piece. Some parts are still reasonable, some are not. I just got a YHM gas block for $13 and a mid-length tube for $12 with a pin, so I could change a carbine into a mid length. Barrels are more expensive as are lowers, plastics a bit more but not bad.