If rubber scrunges your hand you do not hold it proper. It should NOT slip.
It takes much more to hold a slippery grip to prevent "roll". Roll is the enemy of consistent groups. You just increase vertical dispersion and stringing.
Fingers do not have muscles, they are controlled by your forearm with tendons and the arm needs strength to control barrel rise so the tighter the gun is held, the more tension is on the arm to control rise. Your elbow is the pivot point. NOT the grip in your hand.