Thought I'd give a somewhat limited review of a range session I had earlier this week. Rifle: CZ550 American/9.3x62, Brass Graf's (reloaded at least 10 each), Primer: WLR, Powder: IMR4320.
Distance: 232Normal Vulkan and 250gr Nos Accubond: 228yds (lazer'd), 286gr Nos Partition, and Privi Partizan: 109yds
I have noted that with the lighter 232gr Norma bullets (of who I'm a big fan), that the faster powders (I4895 and I4064) seem to shoot these better than the 250's and the 286s, whereas the heavier bullets seem to do better with a slightly slower burn, such as Varget. I tried all weights with IMR 4320 and seem to have found an optimal powder for all weights as the 232s 5 shot group of 2.02"(4 of those into 1.78"), 250 Accubmonds put 5 into 1.96", the Partitions at 100meters put a 3 shot group into .86", the Privi Part 3 shot groups was 1.01". I did shoot a 5 shot group at 228yds of the Speer 270s a couple of days before and it clocked in at 1.92" (All groups measured CTC).
IMR 4320 burn rate is right between 4064 and Varget, RL-15 being a tad slower than Varget. Loads: 232gr=59.3gr, 250gr=59.0, 270gr=58.8, 286gr=58.4. All loads shot with no pressure signs in my rifle, however I don't recommend any load in your rifle. Haven't chrono'ed these yet but the 250s seem to carry very well at the longer ranges and would would be the bullet of choice for me....BobG in VA

BobG,

Thanks for posting. Interested to see what velocities you're getting. The 250 Accubond is going to get the nod in my 550. Varget or Ramshot Big Game will be tried first. Still waiting on custom dies from Lee.

In the ones I've shot, Big Game seems to be the powder with 286's. 65 grains will go just not quite 2500 fps in most reading 2475-2480 with great accuracy. It is also perfect for a .338-06.