On February 8, 2001, approximately 1420 mountain standard time, a Piper PA-12, N7940H, registered to and operated by a private pilot, and being flown by a commercial pilot, was substantially damaged following a loss of control and nose over during a touch-and-go landing at Gallatin Field, Bozeman, Montana. Both pilots aboard were uninjured. Visual meteorological calm wind conditions existed and no flight plan had been filed. The flight, which was reported to be a pre-sale checkout, was operated under 14CFR91, and originated from Bozeman's Gallatin Field approximately one hour earlier. The commercially certificated prospective buyer, occupying the front seat, reported that he was executing a touch-and-go landing to runway 12. After a normal approach at 60 miles per hour and full flaps the aircraft touched down. The pilot reported that the aircraft "...veered right, then hard left..." and that he "...attempted to correct with full right rudder... ." He then "...applied full power in an attempt to get [the] acft flying..." and that the aircraft "...left [the] rwy below flying speed, the tires sank into the snow, [the] acft tipped up on the nose & then onto its back...." The pilot reported nearly 81 hours of flight experience in the PA-12 aircraft. The privately certificated owner, occupying the rear seat, reported that after a touch-and-go landing on runway 12, a second approach and landing was executed. The owner reported that on the second landing "...we initially were pointed too far right and I believe Ed over-corrected and ended up pointing left toward the edge of the runway. Ed added power to go around and tried to take off before we ran off the left side of the runway. We didn't get off the ground before hitting the edge of the runway (and fairly deep snow) and the snow slowed us down and then stopped us causing the airplane to roll over forward and upside down...."