So I loaded up some .257 wby mags and fired them off today at the range. (new Remington 700 rifle)
Conditions - perfect - virtually no wind, nice sunny day warm temps.
Used 1F brass that was full length resized in new Hornady dies.
CCI 250 primers, IMR 7828 powder. Sierra game king 100 gr bullets.
The load data at ww.hodgon.com suggests 73 grains is the max load
Each load measured exactly with a Pact dispenser.
Loaded 3 at each of these weights: 69, 69.5, 70, 70.5, 71. (planning to go to 73 if no signs of pressure, and none of these showed any signs of pressure so I think I will do some more at 71.5, 72, to see where they go)
Average velocity was 3358, 3361, 3399, 3431, 3441 going up the line, and they were all pretty close to the average as well
The accuracy was terrible. The 70.5 load was the best and it was nothing to write home about. Before I give up on this load I will try some more at 70.5 and see if they are any better, maybe some 5 shot groups.?
Question:
You think I should try a different powder or carry on with 7828 at the hotter loads.
I have some IMR 4350 and IMR 4831 and there is data on line for them
(as well I have IMR 3031 and Varget but I have no data for these 2 powders)
thanks in advance for constructive input
Conditions - perfect - virtually no wind, nice sunny day warm temps.
Used 1F brass that was full length resized in new Hornady dies.
CCI 250 primers, IMR 7828 powder. Sierra game king 100 gr bullets.
The load data at ww.hodgon.com suggests 73 grains is the max load
Each load measured exactly with a Pact dispenser.
Loaded 3 at each of these weights: 69, 69.5, 70, 70.5, 71. (planning to go to 73 if no signs of pressure, and none of these showed any signs of pressure so I think I will do some more at 71.5, 72, to see where they go)
Average velocity was 3358, 3361, 3399, 3431, 3441 going up the line, and they were all pretty close to the average as well
The accuracy was terrible. The 70.5 load was the best and it was nothing to write home about. Before I give up on this load I will try some more at 70.5 and see if they are any better, maybe some 5 shot groups.?
Question:
You think I should try a different powder or carry on with 7828 at the hotter loads.
I have some IMR 4350 and IMR 4831 and there is data on line for them
(as well I have IMR 3031 and Varget but I have no data for these 2 powders)
thanks in advance for constructive input
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