I FIND THAT IF I VARY THE AMOUNT OF PRESSURE I APPLY WITH MY RIGHT (TRIGGER )HAND TO THE WRIST OF THE BUT STOCK, WHILE SHOOTING FROM THE BENCH, THAT I GET BAD VERTICLE STRINGING. AS RIGID AS THE CONTENDER CARBINE IS, IT MIGHT GET SOME FLEX. MOST GUYS TEND TO LEAN IN ON THE WRIST, TO GET THE CROSS HAIRS UP TO THE TARGET. THIS WAS HOW I WAS TAUGHT TO SHOOT OFF SAND BAGS, FINE FOR A FULL STOCKED RIFLE, BUT BAD NEWS FOR A CONTENDER (IN MY EXPERIENCE).
I FOUND THAT IF I SHOOT THE GUN FREE RECOIL, LIKE THE BENCH REST GUYS DO, THE VERT. GOES AWAY! I KNOW THIS SOUNDS AWKWARD! BUT IT WORKS.
WHEN SHOOTING OFF HAND, IT'S NOT A PROBLEM. AS, THE RIFLE HANGS THE SAME WAY, FOR EVERY SHOT.
GOOD LUCK!
COOPERSHOOTER.