Phil, I think a lot of stocks cracked behind the side plates because of modern shells being fired in them, and in some cases too much oil applied to the wood and it seeped in around the side plates. If yours is not cracked, I would shoot low pressure shells in it, nothing higher than 8,000 psi. If it is cracked some suggest acra-glassing them. Our own Dr. Bill on this site is the man to see and talk to.