Originally Posted by adkins
I hear about barrel steel alot does any body know the difference in 4140 and 4150. Twist rate is 1in 9 as far as proper assembly not sure everything seems fine gas key looks staked just fine to
Really, after your purchase is not the time to start asking the difference in barrel steel and twist rate. Plus a score of other specs. That should be determined in your initial research. Stag does offer 4150 and 1:7 in their $100 upgrade package. Do you need it? Maybe, maybe not, it depends on your application.
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