Just got some new aluminum screens, 39"x50" 305 yellow dyed mesh, stretched to 22-24 newtons.
We run speedball mostly, straight. For our darker colors, we add matte TW black.
We've always run 305's and never had any issues, even on old screens. These screens are brand new, been degreased 3 times a piece. The only variable in this whole equation is the screens.
We wet the screen prior to ink application, and we run fast. We're getting this almost instant dry in the screens. If we do a double hit, it completely clears the screen. Ink consitency is thin to medium.
On our other 305's everything is totally fine and perfect.
Below is a picture. It seems to get worse closer the center of the squeegee.