Question re: barrel steel grades for L.C. Smith's A friend has a 1909 era 12 bore Pigeon Grade- DT AE- straight hand stock splinter forearm- 28" London steel barrels-a beautiful pre-1913 mfg. middle grade Smith-Parker had various grade names for their barrels-Jack O'Connor wrote in 1965 they were all the same metallurgy-is this also true with Smith barrel steels? Thanks