[ThunderCactus]

The magnus effect doesnt even work at high speeds, in the way we're using it.
And the high barrel pressure keeps he BB centered, and the magnus effect not working.
If the magnus effect was strong enough to lift the BB in the barrel, then it would start acting immediately as it left the barrel, but the magnus effect doesnt come into play until about 50ft out. Then its a very gradual increase in effect as the BB slows down and its able to move more air around to generate an airfoil.

But what makes it really impossible in high pressures is the BB is being PUSHED by the air. Air is pushing past the BB and bleeding past faster than he backspin can move air. At 400fps on a short barrel, a BB would have to be spinning fast enough to push air backwards PAST a 90-120psi compression wave in order to start generating lift.

The magnus effect only works at certain speeds where the BB can actually grip and move air in the direction it needs to in order to create that effect.
If the BB is travelling faster than it can generate an airfoil effect, then it wont generate an airfoil.
The slower the BB is going, the more the magnus effect will affect it.

If you look at a wing at high speeds, it generates lift up until it goes supersonic. Then the aerodynamics change.
If a BB were to go supersonic, it wouldnt matter how fast it was spinning, it would never generate any lift.
And if you have a pressure wave flowing back to front over your wing which outpressures anything in front of the wing, its never going to generate any lift.