Just got this in the mail today. Slider wasn't moving at all. Took it apart and was full of dried grease. Put it back the way it came apart and with the two screws tight won't move at all. Loosened the two screws a half turn each and squirted some breakfree oil to lubricate things. Still no movement. Kept doing the half turn thing and the spring kept coming out of the block that sits between the ladder. So took it apart and used some 600 wet or dry silicon carbide paper to polish the bowed section of spring and hoping to remove some of the scratches. Put it all back together no joy. block moves freely between the slot in the ladder. Could it be possible that the spring with the bowed side should not face the ladder?. All of the dried out grease is gone with some Hoppe's and a fine brass brush. Sight is in excellent shape and ladder it self is not bent. Seriously don't think you'd have to loosen both screws from tight to set windage and elevation and then tighten. It is a carbine sight with C stamped on one of the ears where the elevation notches are. No need for anymore grey hair cause I like what little i have. Any all all help or suggestions are appreciated. Mods, dodn't exactly know where to put this so if you feel the need to move it feel free to do so. Thanks Frank