Welcome from Robeson County.
Miss Mabel seems to like the Federal XM80CL and it is about .60/round.
Front Line Defense is near to you. They have a 1000 yd range and classes that will ensure you can make life miserable for the 12"x 18" target at the end of it.
When Tony takes apart the gas block lock, pay attention, when you put it back together the timing will be off if you have it on backwards from its original position.
Ask me how I know.
Tonyben3 is a very valuable source for us newbies to M1A's