Take a video of your grip while shooting and we could probably tell what the problem is. Sometimes you need a couple of range trips to “become one with the gun”. It certainly is not the same as shooting a plastic semiauto. That barrel is a monster and the recoil is definitely a different animal

You had hogues originally, Maybe the finger grooves on the hogues are not what you needed anyway, forcing your fingers or hand into an uncomfortable position.
Im not entirely sure of your problem but hogue also makes a device called a handall which fattens up the grip or possibly consider gloves with padding where you need it which in effect fattens up the grip as well.