I wanted to get any thoughts I could about polymer frames on the bigger AR's. My friend thinks the 6.8 will tear up the lowers. The gun store by me says the only issue there should be is the way it will look. The only reason I ask, is I can get a RRA upper with a plumb crazy lower for $660, and I'm a budget shopper. It will only be an extra $40 for an aluminum frame, but like I said, I'm a budget shopper. Any thoughts?
I'd also pay the extra $40 for a standard forged lower. My only experience with a composite lower is the Bushmaster Carbon 15 and it's definitely a light use gun, and probably similar to the Plum Crazy lower. The C15 does have a standard metal LPK though.
The biggest issue with assembling an AR isn't so much getting the parts together right - it's getting the right parts together.
US Army 1966-69, VFW Life Member, Retired Geek