Greetings All,
After mentioning the .30-40 Krag cartridge in a post yesterday I was reminded that I really should do some load development for my Martini Krag. What data that is available had already been collected so a bit of a sort out was needed using AR2206H as the load would be a light one due to the rifle action dating from 1881. The Hodgdon on line data has been my go to scource for some time so in we go and pull up the data for the 150 grain. Max loads were 42 grains of H4895 (aka AR2206H) for 2,575 fps and 36 grains of IMR4895 for 2,435 fps at 39,700 CUP. Crikey! A quick surf on Load Data dot com found the IMR data in Handloader 62, published in late 1977 so this is old data. Hodgdon did not list any data for AR2208 (Varget), probably one of the best suited to the cartridge! Perhaps this data is old as well.
A more thorough search for data turned up loads for the 150 grain from 46 grains of 4895 (WW2 surplus powder) for 2,766 fps in 1970 Handloaders digest! Thats over max for a .308! The lowest was the IMR load mentioned above with the balance spread out between. Looking a bit harder all but the IMR data was shot in Krag rifles which seemed to have loose bores and long throats. My ex target barrel has a tight bore and a reasonably short throat. The IMR data was obviously shot in a pressure barrel which would be similar. Suddenly the IMR data does not look so wimpy.
So where too from here? I already have some handloads using 32 grains of AR2206H and the Hornady 150 grain RN projectile which would be a sensible start load based on the IMR data. These shoot well, around 1 MoA, so will be chronographed and a likely final load calculated. The aim is for a load producing a bit over 2,300 fps and low pressure with good accuracy so I can use it in some 100 metre target shoots. I am sure glad I didn't try any of those other loads.
Regard Grandpamac.
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