Re: Ar - 15
I was advised by my local AR15 dealer and gunsmith who specializes in AR's to stay away from the 24" heavy barrels as they tend to crack uppers. Again, no first hand experience but a lot of respect for the source.
I bought the RR varmint EOP in a 20" heavy barrel and couldn't be happier. It shoots 69 grain SMKs at 1/2 moa all day long. The 69s are pure murder on coyotes as well.