Odd, maybe he was just practicing, but the photo of Fredrik Axelsson on the HAM article shows him using a chair with a back rest... See rules below. Am I just being picky?
Rules:
-No Tripods
-No Rear Rest
-Pellets Only
-Scope Magnification maximum of 32x
-No Challenging of targets
-Any shooting position is allowed within marked shooting area
-Bipods, shooting sticks, and monopods are allowed (2 inch maximum diameter base)
-No chairs with back allowed