ellenbr----Raimey,
The GBP powder charge stamped on rifle barrels is 2,579 GBP. Again, that is over, of course, st mG, steel mantel bullet. Regarding all this, additionally, what, if anything, can you tell me about this particular military flake powder they used for proof at the time? Do we now know anything to speak about, regarding its burning properties, pressure characteristics, etc.? Best, Jack