Finished replacing hardware store orings with the proper orings, as well as opening the valve some, extended the probe, and polishing the hammer last week. Nailed 2 cow birds the first time out shooting with it. Today I started with a pumper on 2 grackles- missed both, so switched to the QB79 and started stacking game. Spotted this garden raider and got a 36yd headshot lined up, flipped him for a loop thats for sure... picked up the bird at 25yds, also pegged 3 more grackles right before dark. I am majorly impressed with this thing (1st step away from crosman pumpers), stacks crowmags and 10.5 premiers at 25yrds.