Produces a rich authentic old-style brown finish for original or replica firearms. PLUM BROWN Barrel Finish is ideal for restoring antique guns muzzleloaders and other metal antiques. A durable protective and attractive finish that’s simple to apply. Just heat metal with propane torch or other clean convenient method and apply browning solution with sponge. Immediate results no waiting for old-fashioned slow rust process which can take weeks to finish. – Produces a rich authentic old-style brown finish for original or replica firearms. – Durable protective and attractive finish that’s simple to apply.