Greetings ladies and gents! A couple of weeks ago, I finally joined the ranks of the AR owners. I discovered a Rock River lower at the sporting goods store in my hometown. $150 later, I had my birthday present. I have a few questions as I start my building process. Well, one really, and it has to do with barrel twist rate. I'm sure this is a topic that has been done to death. I understand that the 1:7 barrels are ideal for bullet weights up to 80 grains (I've shot Black Hlls 77 grain before, great stuff). That being said, how will it handle lighter weight rounds, say the typical 55gr FMJs? Wish me luck! Wanna kill these ads? We can help!