Really fascinating thread on the MKVI markings - I recently got hold of a PPC with MKVI on the range drum - first reply so hope I can work out how to upload photos - and was chatting to Roger on email a week or so back. Not sure if this might be useful to the discussion - My one has the standard 1915 patent rings and rifle number of R4878 (assume that was standard SMLE serial format - would the CLLE have the same numbering format?). Not to say of course that the rings might not have been put on later - there does appear to have been some slippage from original marks on the tube although what I assume is an armourer's orientation nick is still aligned. Assume if there was a batch specifically made for the CLLE's, would this have been separate to the specification SA 390/- 4/05/1915? (That does specify SMLE MkIII). However, Ian Skennertonicon does mention in the Lee Enfield Story that a number of CLLE's were fitted with optical sights for TF units - assumed Latteys etc, so possible that some may have been scoped? Would have been a bit of a logistics tangle having to supply MkVI rounds if the rest of the unit was standardized on rifles optimised for MkVII ball.