Re: 338 Norma Magnum
Another report from the range today. The chart listed above does seem to give loads on the light side, but I guess that also means its safe.
My goal is to find a powder delivering over 2700 fps without excessive pressure (would like to be around 2850 if possible). Todays loads were all Norma Brass, Federal Match Primers, and 300gr SMK's seated .002 off the lands.
Today H-1000 and IMR 7828 SSC was tested with a chronograph at 100 yds. The biggest thing I noticed was that with a 10 grain spread in 10 different loads for pressure tests the groups were suprisingly small.
Here is the H-1000 from 74 - 83 grains:
74gr 2298
75gr 2299
76gr 2377
77gr 2388
78gr 2412
79gr 2498
80gr 2501
81gr 2521
82gr 2549
83gr 2588
I did not fire any of the rounds I had made for groups with this powder because I was seeing some minor flattening of the primers at 83gr, and still did not have the velocity. This powder was also a PIA to work with, did not meter well at all, the kernels are large.
Here is the IMR 7828 SSC from 70 - 79 grains:
70gr 2377
71gr 2393
72gr 2482
73gr 2522
74gr 2545
75gr 2594
76gr 2641
77gr 2686
78gr 2714
79gr 2741
This is the best powder I have tried yet. At 79gr there was still no sign of pressure, for tomorrow I've loaded in half grain increments to 82 to see what that will do. This group size was wild considering each shot was loaded one grain higher than the one before. This powder meters well and is easy to work with.
Here is a 5 shot group with 76 gr, not the best velocity, but had to start somewhere.
Here is a 5 shot group with 77 gr:
Here is a 5 shot group with 78 gr:
Here is the 5 shot group with 79 gr:
Still getting used to the light trigger, and am confident that the rifle would put some of these groups all in the same hole with a better trigger puller. Looking forward to tomorrow with slightly higher loads, and some extra 79gr loads to shoot at steel at 400 yds.
Witt
