So here are the two types of roll pins that both fit the roll. The simple pin is from the Trojan. The screw and pin is from a hammerless gun. When you look at all those threads, then add moisture and 100 years you can imagine why it is so hard to undo the screw which is why we see so many buggered screw heads on the roll pin. Never really any need to remove these pins unless there is some major catastrophy.
