Greetings again,
One powder I have had good results with in the 7mm-08 is AR2208. In a 19 inch barrel 42.5 grains of AR2208 and the 140 grain Remington Corelokt chronographed a little over 2,700 fps. Hodgdon offers different data for the 139 grain Hornady and the 140 grain Swift which is a longer and harder projectile. The former is more appropriate for the Corelokt. 41.5 grains of AR2208 and the 150 grain Remington Corelokt chronographed just under 2,600 fps. Once again Hodgdon offers two sets of data for the 150 grain and the Sierra data is more appropriate for most projectiles that have a lead core.
A word of caution regarding AR2209. Current lots seem to be significantly faster those from before 2,000 so loads need to be treated with some caution. This includes the current Hodgdon data. You will likely lose about 100 fps with your 20 inch barrel from 24 inch data so assuming that you are still using AR2209 2,900 fps sounds about right.
Regards Grandpamac.
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