needs stiffer hammer spring or slight bumper on powertube since it requires a hard pump stroke to catch bolt to hammer. Maybe the spring is too heavy? Take sl-682 style spring no nelson spring. Internals are non adjustable. Has sight post on top of pump handle and back loop sight. Back bottle valve screw is rusty. Serial on bottom of grip frame is 1727. Barrel has cool knurling (not sure if that is a good idea to have under the pump? Barrel looks like it's sl-682 compatible but needs a bevel for the bolt. Chrono Results (around 8-5-2012) were: 259, 262, 265, 247, 255
