Looking for methods to remove and save 125 year old British gun case label.

Thanks for advice.

Use a steam wallpaper striper, or any other method that you can apply steam to the label. Because at that age it will be held on with an animal derived glue. Though not as quick as steam you can apply a wet cloth but this can be fraught with dangers like not loosening the glue uniformly so you might tear or move the Ink in the label trying to remove it if a paper one.

Second on the steam wall paper stripper, be patient and try not to wet the baize as the animal glue will loosen and the cloth will lift.

Damp cloth with a steam iron, just like steaming out wood dents.