I am wanting to shoot in military bolt-gun matches at th club I recently joined. To that end, I have done some work on the Mosin-Nagant that I have, smoothing the trigger, etc.
I want to shoot, for practice, some of the surplus ammo I have. I have two crates of surplus that I purchased back when they were less expensive (and available). One of those crates is a 1951 Russian (plant #60) light ball, copper-washed steel case, lead core steel-jacket.
I pulled the bullets from 10, weighed the powder. It averaged 49.5gr. I dropped the charge 15%, and re-assembled the rounds with 42gr.
I shot those ten rounds over the chrony, got 2454 fps avg, with a spread of 32 fps, and a deviation of 15.8 fps. Those numbers tell me I am getting good ignition, no problems there.
I have loaded up 5 more, to shoot today, dropping the charge another 2gr, for a 40gr charge. This is approx a 20% reduction from the initial charge. I want to have practice rounds, and I already have this ammo, so I want to make it shoot without beating me up. I don't need 2900 fps to kill paper.
My questions -
This powder looks for all the world like IMR4895. Looking at my manuals, Lyman #48 specifically, it is giving me velocities in line with a charge of IMR4895. I do realize that the 1950's Russian Army did not contract out its powder manufacturing, and I do not have IMR4895, or a cannister grade anything. But, if it walks like a duck...
That being said, Hodgdon tells me that IMR4895 cannot be reduced "too much" (unlike H4895), because one will run into ignition problems, resulting in possible problems too horrible to contemplate. Nothing specific on what "too much" is.
At what point should I consider a Dacron filler ? The 40gr charge still fills a good portion of the case, perhaps 80% (just eyeballing it). I've seen some on here using a 20-ish grain charge of IMR4895 with cast and a dacron filler, to get very good results.
Comments ?