Just meaning that different guns will "like" different pellets, even guns of the same model. A wadcutter, or flat-faced pellet, is the standard/cheapest/most common kind. It just means a flat face, not a rounded, pointed, or hollow point face. I have the Crosman Quest 800 in .177 (similar to yours), and it's my go-to gun for yard starlings & grackles. I nailed a grackle yesterday at over 35 yards... he dropped straight to the ground. This was with a Gamo wadcutter pellet - yes, even though I preach against Walmart pellets for top notch accuracy, they work fine for reasonable accuracy. The wadcutters NOT ONLY are very accurate, but they actually kill birds more effectively than a rounded or pointed, because they transfer a lot of energy & expand, and you don't need much penetration to kill a bird. And for competition, you want accuracy, period, without regard to killing power. If you're shooting past 10 yards, outdoors, you MAY want a rounded nose pellets to fight the wind better (heavier pellet). Look at that picture of the RWS pellets in the variety pack that I linked to above. Two of them are wadcutters (the 3rd and 4th from left), one is pointed, one is hollow point.