BHM was a Springfield inspector. All pre-WWI Rock Island rifles were inspected by Conrad Nelson (CN). His stamp consisted of a "script" CN over the date accepted.
Look on the very forward tip of the stock (the "wedge" you see when looking down the barrel). Springfield stocks had a 1/8" S while Rock Island ones had a 1/4" inch S.
BHM was a "real" person -- there just is no record (again, if my memory serves me) of who he was.