If 1 MOA = 1" at 100 yards, then would be 10" at 1000 yards - mighty small group indeed!
But 2.7" at that distance, that would equate to 0.27 MOA.
Allowing for wind shifts amongst a host of other variables & no doubt the coriolis effect (that would come into play as well at that distance i guess) - amazing shooting to say the least!