338 SHERMAN MAX

I run 540 and 550 in my 338 SST. I think 550 is close to 100v and 6.5 StaBall. But not sure how similar the energy content is. I would think 550 or RL 19 would be good. Maybe 555, but I think it is a little lower energy content.
 
6.5 staball has been right with 100v for burn rate with what I have used but the 6.5 staball doesnt have the energy content of 100v. I have some n555 but havent opened it up yet. Still waiting for a new barrel to replace the dud I got for my first try on my 338 max. I was concentrating on the 265 LRAB which is what I hope I can get to work when I get it going again.
 
How is it that you guys are getting 3000fps with a 230gr eld but the 338 wsm won't even come close?? I'm sure the Efficiency comes into play but not that much. Have these rounds been pressure tested??
 
How is it that you guys are getting 3000fps with a 230gr eld but the 338 wsm won't even come close?? I'm sure the Efficiency comes into play but not that much. Have these rounds been pressure tested??
The WSM really needs at least a medium action to work correctly. A wsm in a short action will loose powder capacity with modern long high BC bullets. Keep in mind the WSM as not designed for the long bullets common today and was just simply more muzzle for the average deer hunter. The Sherman line of cartridges is optimized by action type to avoid handicapping the cartridge in the wrong action like so many other cartridges.
 
Getting back to load development on this one. Burnt some Hybrid 100v and StaBall 6.5 today. Oddly enough they both pressured out for me around the same speed. Results looked like this:

250 Bergers
Fed 215 primers
Grains of 100v - FPS
67.0 - 2751
67.5 - 2755
68.0 - 2772
68.5 - 2804
69.0 - 2817
69.5 - 2820
70.0 - 2843
70.5 - 2862 (noticed bolt lift here and stopped)

To maintain a constant BTO after 68 grains required adjusting the seating die or multiple strokes of the press.


250 Berger's
Remington 9 1/2M primers
Grains of StaBall - FPS
68.0 - 2699
68.5 - 2747
69.0 - 2755
69.5 - 2769
70.0 - 2804
70.5 - 2833
71.0 - 2839
71.5 - 2856 ( little bit heavier bolt lift)
72.0 - 2853 ( bolt lift increased again)

This stuff filled the case nicely. I had more room to go at 72.


Probably get back to it next weekend and try shooting some groups.
 
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