I believe the problem with factory rings is with the 30mm Ultradot 4 which I have. I use the Weigand rail. For the record I would probably not get the Ultradot 4 again, but the standard 4MOA Ultradot.

Vance in AK.

Matthew 6:33
"But seek first the kingdom of God and His righteousness, and all these things shall be added to you."