I recently got a good deal on this revolver. It appeared to be in good condition. Trigger was a bit heavy (normal for rimfires, I'm told) , but relatively smooth. Lock up was very tight. Took it out to the range with my boy and nephew and enjoyed about 100, maybe 200 rounds before the double action pull started to bind. Ejecting empty cases also became very difficult at this point as well. Later, at home, I put some oil on the cylinder face where it was collecting the most powder and where I suspected the tension to be taking place. The trigger loosened up a bit but not quite like it was when clean. This is the first rimfire revolver that I've owned, so my question(s); 1) Is this happening because the .22 LR is just plain dirty to begin with, and therefore I may just need to clean the gun out every hundred or so rounds? 2) Is there something else wrong with the gun? 3) Has anyone experienced a similar problem, and with which 22LR revolvers?