I currently have a TM desert eagle hard kick, and I found that even with the hop up off, the BB still curves upwards over a distance (~20-30 feet). For a target like a pop can, I have to do a very solid 6 o'clock hold (have I got this definition correct?) to be able to hit the can in the middle. I've had similar issues with some other GBBs before. Hop up needs to be adjusted way down, and even then I have to aim a bit lower than the target point.
Could this be because I am testing from an elevated position (second floor)? The slanted angle causes the BB to be pulled towards the ground differently than when the BB is going straight (I'm no physicist...
It seems even if I am at the same level as the target and shooting straight out, the increased hop up I'd have to do would be tiny. I mean it's fine if I have a way to shoot straight every time, but it just seems odd that I'd only be using less than a fifth of a turn on the dial to get the gun to shoot accurately.
Anybody that's mastered the art of hop-up adjusting have any suggestions?