barrel lengths?

[indyjohn]

If I shot a six-inch group at 600 yards, I'd giggle like a little girl. Even more than I usually do, I mean.

I had to go look it up to be sure I wasn't talking out my arse. NRA Highpower rulebook says the X ring of the 600 yd target is 6" in diameter. If I don't have the wind to contend with, my AR & M1A both will put rounds in the X ring as long as I want them to!

http://www.nrahq.org/compete/RuleBooks/HPR/hpr-book.pdf