I have used Acraglass with floc and black pigment powder to fill beetle holes. I fill the holes with the epoxy on a teethpick, cover with tape and let it cure with the butt down. After hardening remove the tape, file, sand with a hard flat block, burnish with steel wool. Ihen apply Truoil, let it dry for a day and burbish/polish with 0000steel wool, this may take more than one coat. I have used this technique on many, many pieces of horn buttpalates and grip caps, carefully dune the repair is hard to see. Jerry