I use a spent shell casing to tear down my Kel Tecs. Quite often I get the same stain. I wouldn't even be concerned just normal holster wear will get it off. You can use solvents if you feel the need.
"I do not aim with my hand; I aim with my eye. He who aims with his hand has forgotten the face of his father.
I do not shoot with my hand; I shoot with my mind. He who shoots with his hand has forgotten the face of his father.
I do not kill with my gun; I kill with my heart. He who kills with his gun has forgotten the face of his father."
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