True!

But it is also true that all rifles are individuals, and what proves to be a maximum load in one may be quite mild in another, and vice-versa!

A load which proves to be maximum in the rifle which was used to develop the loads published in any given manual is just that-maximum in that rifle. This does NOT relieve the handloader from testing worked-uploads in his/her own rifle to ensure that the loads listed as maximum are not OVER MAXIMUM in that person's rifle!! In addition, just because a load is labelled "MAXIMUM" in some manual does NOT mean it is MAX. in yours!!

For example, I have a .30/'06 underbarrel on my Heym O/U combination gun, and a Ruger No. 1 in .30/'06. Boththese guns will handle a pretty warm 200-grain load without a hitch. But I cannot shoot this load in my .30/'06 TCR barrel-it will not stand it! Extraction is unacceptable, and primers areextruded into the firing pin hole. So this load is OVER MAX. in the TCR, and under MAX in the other two...... and so it goes!