Yes thats what it means do NOT EXCEED MAXIMUM LOAD.
In the case of the W231 recipe, the resulting speed is 200 fps slower than some of the other powders listed for that bullet, with 6000 PSI lower pressure. That would lead me to believe that the "max" load isn't really the max, but I also know that increases in chamber pressure aren't always linear beyond a certain point.
Do yourself a favor and follow the recipe. I can assure you you DO NOT know more than the folks that put all this load data together for us do.
NRA Life Member, NRA Range Safety Officer, IDPA Safety Officer, USPSA NROI Range Officer
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