Start at 96.0 gr and work up from there. I have seen some lots of US869 top out at 105 gr whereas others have allowed up to 109 gr depending on your area but 96.0 gr should be plenty safe for a starting load.
In fact you may actually get some minor hang fires at this level but this is rare. If you do, add 2 grains to the starting load and start working up from there.
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