So question for you guys who have had your ACR's longer than I; When cleaning your rifle do you usually take off the barrel or leave it attached to the reciever? I've heard from a few owners that they leave theirs on so they dont have to worry about re-zeroing. Another thought that crosses my mind is each time you take it off and put it back on i'm sure it causes wear right? Has anyone had any problems from consistently removing their barrel?