Yours is a straight up legit MK IV rifle transferred from a Brit arsenal in India to Nepal in 1908. It started life as a second pattern of the never issued Enfield-Martini (EM) in .40 cal. Save for the pattern room, all EM rifles never left Enfield before being converted to MH MK IV rifles in 577/450. The EM came in 2 patterns. The first pattern had a number of receiver features that made the receiver uneconomic for reuse in the MK IV program and hence they used new receivers with the "IV" centered under the lock viewer's mark. The second pattern EM rifle receivers were reused and converted to "IV" markings by striking a "V" next to the "I" on the receiver as stamped when it was an EM rifle, making the mark off-center. The third pattern MK IV rifles were assembled from previously unused parts and don't show the signs of conversion, such as the lock markings, the plugged buttstock and "EM" being struck out on the block and a few other parts. We used to follow the guru of Martinis (Skennertonicon's) labeling of the three types sequentially as described as "A", "B" and "C". However this has been found to be in disagreement with recently uncovered notes from Enfield made during the conversions. Let the academics argue which is which, since it doesn't change what they were and what they were converted to.

The Nepal shipments involved rifles mainly held in Brit arsenals in India and the rifles were refurbished/repaired as needed prior to being shipped. The MK II rifles generally went first and the MK IV rifles followed. It appears that the main shipping date for MK IV rifles was 1906, so the subject rifle would have been one of the last ones shipped. Many of the Nepal rifles show part changes not in keeping with the above described rework of the EM to the MK IV. This can be ascribed to the simple fact that during the subsequent refurb/repair in India there was no incentive for workers to keep a given rifle's parts together to satisfy collectors a century hence.....after all, to someone working the refurb, MK IV parts were MK IV parts. It is all part of the rifle's history and does not make it a "parts rifle."

As for the exterior barrel pitting, after handling literally hundreds of these rifles I've never seen one with pitting deeper than the typical dovetail slot cut for sights....with most of the "nasty pitting" being much much less. There is a lot of quality steel there and I wouldn't hesitate to shoot any of them. The 577/450 operates at around 26,000 psi...or 2,000 psi above the venerable (and even older) standard .22 long rifle. This is a far cry from the modern cartridges operating at twice that pressure. Everyone must do what they believe is safe, but exterior barrel pitting on a MH is the least of my concerns in shooting antique firearms.