I have a VTC (WWI Volunteer Training Corps) marked 303 Martini. The VTC was a home guard in the U.K. during WWI. Did things like guard munitions and railroads. Basically until some units were issued P14's later in the war, they privately purchased or used what they had in firearms, such as carrying shotguns. The more affluent units might have all the same caliber and type of rifle. I've seem multiple photos of VTC units carrying Martini's. My Martini was made by the gunmaker William Ford of Birmingham.
So far, I've been unable to find exactly what the "D" stands for. Probably the British county or U.K. city the VTC unit was based in. Example: It could be Dublin, as that city had a VTC unit. The county of Durham had a large VTC presence. I've written Durham, but not answer so far.
Anyway, while I've successfully been using IMR4895 with the Lyman 314299 in a mild load (30.5gr) giving 1788fps and shooting to where the sights are aimed, I thought lets try this jug of 7383 that's been on hand for years. Loaded up 30, 31, 32, 33, and 34 grain loads. CCI 200, mixed brass, but mostly HXP, 3.08" oal. Only choreographed 1 shot with each load and got:
30gr 1479fps
31gr 1468fps
32gr 1595fps
33gr 1652fps
34gr 1718fps
No pressure signs and a few grains of powder left in the bore and fired case after each shot. I then fired groups with each of the 5 loads. At 34gr the bullets hit to the sights and grouped the best, so I stopped there. Quite the 7383 smell when you eject the fired case and the smoke blows right into your face. Also got the "what are you reloading with, it stinks" comment at the range this week. Anyway here's another use for 7383.