Martini Henry iv modal A or B

[Richardwv]

As Douglas states, the MH MK IV comes in 3 distinct patterns. However such were not distinguished in the era, but have been so named by collectors. The first two patterns “A” and “B” were rebuilds of the .40 Enfield Martini rifles that were never issued owing to the dawning obsolescence of black powder rounds with the pending adoption of the .303. It was thought that two BP rounds plus the new smokeless round would just present logistic problems and it was better to rebuild the unissued rifles as 577/450 Martini Henrys in a new configuration based on the EM rifles then unissued in stores.

The 21,755 pattern “A” rifles were based on the first version of the EM, which had a number of features, such as the “quick loader”, that made reuse of the receiver infeasible. Therefore the pattern “A” rebuilds utilized new receivers easily identified by the “IV” being centered under the lock viewers mark. Also the barrels that were reused had a very short knoxform, which perhaps is the major signature of the pattern “A” rifles at first glance.

The 42,902 pattern “B” rifles were based on the second version of the EM and reused the EM receiver, which was initially stamped as an EM MK I. When reassembled into MH MK IV rifles, the receivers received the addition of a “V” to the right of the existing “I”, leaving the MK “IV” designation slightly offset to the right of the lock viewer’s mark immediately above it. Also the barrels have a much longer knoxform and use a ramped front sight negating the ability to use the socket bayonet.

The 35,344 pattern “C” rifles were made of all new parts. This does not mean that they where made solely of purpose made parts for the MK IV, only that the parts used had not previously been assembled into a rifle. As such many new parts used had been originally manufactured for use on the now extinct EM. I have yet to see a MK IV buttstock that did not have the hole plugged for the cup to hold the shorter EM lever. They exist, but I have yet to see one in person. The pattern “C” is very close to the pattern “B” with two exceptions. First since the barrel was not reused by cutting off a thread and reboring/rechambering, the knoxform and overall barrel length is approximately one thread longer (0.125 inch). Second, the new receiver shows the “IV” centered under the lock viewer’s mark.

It is uncommon to find a MK IV that hasn’t been through a rebuild and it is important to remember that the patterns described above were not officially recognized. As such during rebuild the “parts is parts” philosophy is in evidence, with parts from one pattern being used on another, further confusing the collector. Also since the conversion from EM to MH MK IV pattern “A” and “B” occurred concurrent with the new pattern “C” production, there are indications of some mixing of parts even in initial assembly, particularly in regards to using a new barrel where a rebored/rechamber one might have been discarded due to defects in reworking a barrel to 577/450. As such questions concerning whether a given part is "correct" for a given rifle is nearly impossible to answer. In the end any MK IV part can be considered period correct for any MK IV rifle.