Ive shoot some PR 260gr .40 dead center bullets in my 1-20 and they shoot good but you have to push them with 120gr BH209 to get good groups less they open up this is not a bad twist just people just have to take the time to see what shoots in it and the sabots are better today then when they first came out I remmenber when i first got this gun in some were in the 80s almost give up on it