I have a 2013 SP101 22LR that I installed the pre-2011 spring kit #17113 adding an 11# to that kit. With the 8# trigger spring and the 11# hammer spring it was fairly reliable, an occasional FTF. I did polish it up inside and added a shim kit! I recently found that Wolff came out with a newly engineered kit #17114 for the post 2011 guns like mine. So I called Wolff and they confirmed that this kit was specially engineered for the new model .22LR. The lightest hammer spring in this kit is 13# all the springs are shorter than the earlier kit. I just installed the 13# spring the pull is still heavy but I understand it needs to be to set off the rimfire cartridges. We use this gun to kill rattlesnakes around our home with bird-shot and the problem is my wife has a tough time pulling back the hammer, even worse trying to use it DA. Has anyone come up with the "Just Right" combo for this .22 revolver? I would like to hear from those of you that have experimented with the spring kits, how to get a lighter pull yet a reliable ignition! Thanks!