With these old eyes, I can hardly see the brass bead at the end of my rifle* barrel . So I put the barrel vertically in a vice and , with a paper clip as an applicator, applied a small drop of crazy glue to the brass bead. Then I dusted some white pigment ( from a craft store) onto the glue and, presto, a white bead appeared. Not sure how long it will last but now I can see the front sight.
* A break-action Savage single shot 30/30 which I don’t want to drill & tap for scope mounts.
* A break-action Savage single shot 30/30 which I don’t want to drill & tap for scope mounts.