That's the famous TC crack...
Any pics to know what I'm looking for.
Get a good BP cleaner and plastic solvent.
What's a good BP cleaner and plastic solvent? Ballistol has been suggested. Shooter's Choice says it removes shotgun wad fouling-it works pretty good on choke tubes with a bronze brush. I was always told to shy away from petroleum solvents with BP-have always used hot water and Dawn dish soap, rinsed with almost boiling. While still warm a patch with wonderlube 1000+.
Steel-I'd call it the intermediate one with round bead, rear sight has curved slopes to it. The older front sight had a better (IMO) square blade, the rear was square too.
You can learn a LOT from your patch. What condition is the patch in after firing it?
I will search out the patches the next time I have it at the range. Also, your suggestion on loading is good advice-for most things.
Thanks for all the help, I'll start working on narrowing it down.
LHS