The correct wood finish for an 1870's gun stock? well that question limits your choice right away. To have the correct finish you can only use what was available at the time of the guns manufactured. So you are down to Linseed and Tung oils plus a couple of other drying oils having minimum use at the time, with C opal and shellac resins also Pine tree Rosin of various types plus boiled Larch tree sap known as Venice turpentine. If I where given this problem I would use the tried and tested gun stock finish that has been around for a t least two hundred plus years. Starting from bare wood surface t one brush coat of Garnet Shellac French polish fifty percent cut with Alcohol next one brush coat Garnet polish twenty five percent cut with Alcohol, finally one brush coat of undiluted Garnet polish. Doing this the shellac will soak deeply into the wood and will act as a good moisture barrier. using fine abrasive paper or 000 steel wool smooth the surface then using a lint free rag apply a couple of coats of boiled linseed oil to give that dull shine. Finally when the oil is dry apply a couple of coats of wax polish containing a good proportion of Carnuba wax for that looked after gun stock luster.
