Basically what is happening is that the top of the nose of the bullet hits the bottom of the ramp and digs in and causes the gun to jam. It has hit hard enough in some cases to actually split the bullet.
Have you ever had it apart?
When you takedown a Ruger, it is difficult to seat the upper barrel assembly back to nominal spec relative to the lower, which aligns the magazine, and controls the angle that the ammo feeds to the ramp.
Hard to describe, easier to show.
I would either send it back or try to adjust the distance forward/back of the upper receiver.
Rugers are tough if you take them down.