Bill you maybe dealing with a very small base if info. If the majority of 9MM required a .357 or larger bullet accuracy with .355 jacketed would be atrocious. It isn`t. I would think .357 would be the largest anyone would have to go unless you are dealing with a WW11 or older gun from occupied Europe. I recently reduced my diameter to .356 in my guns and have found no difference in accuracy - CZ 75`s, M&P`s, STI and Tanfoglio.
Take Care
Bob