Oxidized grip cap
 

I assume they were bakelite in the 20's? Is there a good way to get the yellow grunge off without hurting anything?

I always thought ballistol might be right but im interested in the experts opinion

Black shoe polish

Steel wool will remove it, but it would be hard to get it all out of the detail and lettering. And it will soften the detail too. If it os something you cannot live with, I suggest some of the coloring methods mentioned above. Or a sharpie.

Ultrasonic cleaner?

That will likely make it worse. Or have no effect.

Ha! Am I the first guy to have the problem or to be concerned about it? Guess I assumed others had run into this before.

It is pretty common. Some guns experience it, some dont. I do not know what chemically goes on that causes it. It can happen with caps and buttplates.

I once tried to put an original lefever buttplate in boiling water to soften it to help it confirm to the curved butt of a stock. Just like you would with modern urethane plastic. The plate instantly oxidized in the hot water. Which is why I did not recommend ultrasonic cleaning.

If it is in fact chemical oxidation, possibly a rust removing solution may have an effect. But I am sure it is not the same thing as rusting metal.

Before bakelite there was gutta percha which normally lightens in hue or shade with age… some caps go almost blondish and it’s not limited strictly to the surface… it can be deep within it.






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From dental work to grip caps and butt plates? Go figure.