Duplicating a cordite load for 303/270?

kombi1976

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The 303/270 was probably the 2nd most popular 303 wildcat in Australia and many rifles, mainly SMLEs were chambered for it.
Cartridges of the World 10th Ed. features an interesting chapter called Wildcats Down Under penned by Breil Jackson, the editor of Guns & Game Magazine which is published here in Australia.
It has many references to firms like Riverbrand, Super Cartridge Co. and Sportco and to inventors like Clive Downie and Arthur Langsford, who was the real inventor of the 17HMR, better known as the 17 Vixen, almost 25 years earlier than Hornady.
It also mentions the work of Australian gunsmith and inventor Jack Black(and I don't mean the actor/musician of School Of Rock fame! :p ).
Apparently Black invented the 303/270 so he could pull the 174gn bullet from a standard 303 Brit military round, neck it to 270 cal and load it with a 100gn soft point.
But most importantly he retained the same load of Cordite resulting in a muzzle velocity of 2850fps.
Hence the 303/270 was much easier to load for than other 303 wildcats and a good marketing venture.
Since this load would've presumably been safe in SMLE type rifles it would be interesting to try and duplicate this load using modern powders.
Does anyone know how many grains of Cordite were used in the MkVII 303 round?
And is there a modern powder, preferably a Hodgdon powder, that will duplicate it's burn rate?
For those interested the dies for 303/270 are still made by Aussie reloading company Simplex and rifles are available from time to time here, usually pretty economically because they were modified military rifles, not factory rifles.
Here's an example:
http://www.cobbsamurai.com/images/firearms/116 BSA SMLE Sporter .303270/index.htm
 
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The .303 MK VII pushed a 174 gr bullet at 2440. P-17 posted the following intersting piece, and he seems to be knowledgable on the topic. Perhaps you should PM him.

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p-17
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Posts: 274 FYI, the predecessor to IMR 3031 was called MR16, I believe. It was developed in 1916 as a single-base powder for .303 military loads. I believe the original military .303 load was something like 37.5 grains of Cordite pushing a 174 fmj at 2,400 fps. However, Cordite was a double-base propellant and burned out machine gun barrels too quickly in the heat of WWI, so they wanted a cooler powder with about the same energy level.

The new load worked out to something around 37.5 grains of MR16 with the same bullet. In other words, essentially the same charge. (This is why some people think that IMR 3031 is a pretty close match for Cordite.) Though I've never tried it, I've heard that this same load works well with IMR 3031.
 
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