There should be nothing unsafe about using a published max load.
I think there is some confusion about published maximums - Are they "carved in stone"?
Sierra puts it this way about their data - and this would apply to
any reloading data in any of the known bullet/powder manuals:
...reloading manuals are not carved in stone. Think of a reloading manual as a REPORT, and you'll be in a much better position to understand this. In essence, a reloading manual says, "We tried this particular component combination, and these are the results we obtained." When you duplicate the load shown in a manual, you're using a different rifle (even if it is the same make, model, and caliber), a different lot of powder (even if it is the same brand and type), a different lot of cases (even if they are from the same manufacturer, etc.), a different lot of, well... you get the idea. There is an amazing number of variables that effect any load combination. With the difference in the manuals, you're just seeing first hand examples. Again, start low and work your load up.