Endshake is not detectable - its tight as a drum.

The strain screw sure looks like it hasn't been touched. I compared it to other Smiths.

The brass is the same, as are the primers, except for maybe a new brick. I only use CCIs.

As a matter of fact, it started after my mid-Winter gun cleaning marathon. I do all my guns in the off season. The cylinders look fine.

Now that i think of it, the only change was the load and the bullets. I used to use 158 SWC lead, but switched to Berry's 158 plated for outdoor use. I guess next time I'll try a box of lead and see what happens...

Thanks for all the help so far...