A lot depends on the gun ,some have screw pins ,some have knock in pins with screw caps or cover plates. Some have blind caps that were screwed in but never intended to be removed so a drill is the only way to get them out. Some have knock in pins that have a driven in blind retaining pin .
As over the years I have jointed hundreds of guns I think I've seen just about every type there is.
Bear in mind that the pin may well wear on more than 50% of its surface area ,so apart from a curiosity surely the best thing is to replace the worn pin with an oversize replacement?
