Originally Posted by max503

My EDC is an S&W 638 that I shoot fairly regularly. Several times/month at least. So yesterday I was at the range and decided to do some practicing with my snubbie. I had loaded up about 35 wad cutter loads for that purpose.
About half way through my double-action practice I noticed the hammer wasn't acting the way it should. Once or twice it didn't come all the way back even though the cylinder rotated. It was cold out. I stopped shooting and unloaded the gun, and worked the action several times. It worked ok.
When I got home, took the side-plate off and found that the lube had collected enough soot and debris over time from firing that it had pretty much gunked up the action. I shoot this gun a lot. Always cast bullets. I keep the outsides and the chambers very clean. But this little lesson taught me that any and every little crack and crevice is going to allow in just a little bit of smudge, and over time that stuff builds up and can cause a problem.
Guess it's been several years since I had the side-plate off. From now on I will take it off every New Years. I'm just glad I didn't find out about this in the midst of a serious social situation.

As a note, a while back I learned about this home made tool which greatly aids re-insertion of the rebound slide and spring. I cannot recommend this tool highly enough. If you don't have one, you should make one. Sorry about the crummy picture. If you need more info about it let me know. It turns a touchy job into a piece of cake.