--I've looked at a lot of wartime Boer guns and have yet to see one with initials stamped on the barrel. It is entirely possible that the letters were stamped by a gunsmith/gunmaker who might have directly ordered the gun from the US. It is also possible that the letters were stamped at some later date. I've seen lots of wartime capture guns in Legion messes over the years--the gun may have been removed after spending years on display in a Legion mess somewhere. In any case, at this point, all this is pure conjecture. It would be interesting to see similarly stamped guns with known provenance, as that would probably clarify things quite a bit. Attached are pictures of typical Boer stamps/marks. Typically, only guns purchased by the Orange Free State (OVS) prior to the war have stamps placed on metal parts.