That's fuggen outrageous. I wonder what the specifics are on how that was shot and with what?
They have a 200 yd underground range at their factory in Sedalia, you can bet it was shot there. In fact they have a number of such group cards on display with all manor of calibers. The "rifles" I saw were Remington 700s with extremely heavy barrels.
BTW, you don't have to be anyone special to tour the factory, my wife and I were near Sedalia last spring and stopped in to their factory outlet to buy some seconds (they have barrels of them). I asked about a tour and one of their techs took about 2 hours to show us all around. Fun and informative.