Ok, Now, do you have a suggestion as to how I can present that to a 75 year-old farmer who only completed the eighth grade?
Well speaking as a 70 year old with a few more miles than the average Iowa farmer of about the same age you are probably wasting their time trying to change their minds. God love them and accept them as the are, misinformed by years of misinformation from ammunition companies, half assed gun experts that inhabit some gun clubs or proclaim themselves experts because that got an article published in a well known but notably slanted Outdoor magazine looking for a sensation article to titillate the masses.
No question that "experts" in print can be wrong. I recently read--from one of the "experts"--that once you have a pressure figure in bars (as stamped on British guns until recently), then all you have to do is multiply x 14.5 and you have psi; therefore comparing "apples to apples" with pressure figures for American guns. Well, in order to compare apples to apples, you have to make sure that none of the apples are oranges. Although the British proofhouses converted from crushers to transducers to measure pressure in the 1990's, they continued to use the old bar figures (850 bar was standard proof) AS MEASURED BY CRUSHERS as their proofmark. (They finally dropped all proofmarks expressing pressure as a number in 2006, replacing them with STD for standard pressure, SUP for superior pressure.) And when you have a pressure figure in bars as measured by the old crusher system, you can't convert it to a psi equivalent by multiplying x 14.5. You end up with LUP (lead units of pressure, still seen in some reloading charts) and not psi when you're dealing with measurements taken with lead crushers. The mathematical formula will not magically convert those crusher bar oranges to psi apples.
