There does seem to be damaged lands just inside the muzzle.
Two things, The tight lead is swaging down the pellets making them a loose fit in the rest of the barrel. I would lap the lead, or bore it out past the tight spot. Then push some pellets through to see if the fit feels uniform going through the barrel.
If all this should work out i would be interested in knowing how you came to work out how you needed to cut your spring. I understand how it is done with an adjustable HSpring, starting with it out and then winding it in until you see the knee but how did you know without being able to adjust the HS and chart the curve.
The lead is still to tight. You don't want it swaging the pellets down, you can see from the flattening of the circumference of the pellet head. You only want to see very light rifling marks, no flattening.