Weighting your R-P brass in interesting.  I just pulled out an unopened bag of Winchester 30-40 brass I purchased about ten years ago (my last bag) and took five random cases and weighted them.  They were much lighter then the R-P brass by about 100 grains!  Here are the weights; 165.7, 165.4, 165.4, 164.9 and 166.8.  I can't imagine that the R-P brass would weight that much more then the Winchester Brass.  I don't have any other cases to weigh as a comparison.  The Winchester cases have lasted a long time but I generally use a light load and anneal them when they seem to get harder to resize.