I have had my g20 for quite awhile now and have never had any issues with it until recently. Several months ago I purchased a 6" LW barrel for it and have been shooting it with a lot of different loads both factory and handloads with great results, it seems to love just about everything I put through it. I decided to fiddle with it a bit and I got a LW spring and rod assembly. I got the new spring and rod put in and it was shooting great for about 30 rounds and then it started with FTF due to obvious light primer strikes. I checked it out and found the little allen head that captures the spring had unscrewed a couple turns. I tightened it back down and it shot great for another few rounds and then the lite primer hits came back. Checked the allen screw again and it was not loose. I could not find anything out of place. I even pulled it down (slide) and gave it a good cleanimng but it was not dirty at all. I put it back together and this time I put the stock plastic rod and spring back in and the same thing, a few good shots and then the light hits again. I then put the stock barrel back on with the stock rod and same deal all I get is clicks when I should be getting bangs. I am completely flummoxed and do not know what to look at next. If you have any advice on where to go from here I would apreciate it as this is by far my favorite pistol and I am going nuts trying to figure this prolem out. Thanks!