When did they start stamping the "T"s on snipers

[rayg]

Thanks Roger, I assumed that the earliest Enfield Trials snipers didn't have the "T" stamped but then I saw the one on Gunbrooker with the "T" stamp and it's serial number was earlier then mine and it threw my thoughts off. I think you explained now were the "T"s were stamped on rifles later by ordnance that didn't originally have it when first converted at the Enfield factory. So somewhere along the line, the Trials "T" in the auction received the "T" stamp but it did not have it when it was originally converted at Enfield or could it have been a Trials rifle that was converted at a later date then mine? Ray