I must be buying the 5-1/2's then, I've never seen any warnings like that before. In fact I find that my current stock of R-P primers are just dandy for .357's in my 1894. If in fact that is the case then I need to start looking for the 1-1/2's then. I have always liked the performance of R-P primers but all those hard ones skunked me pretty good. I always thought small pistol was small pistol and that is that, figgered the number and a half designation was some old tradition from long ago.