Up until last month I used small rifle primers for all of my small primer loads. (near onto 5 years, and over 50K rounds.) Everything from 9mm Luger to .223 Rem., and a few small primer .45-70 Gov't cases. When I was low all I could find were small pistol. So now my small pistol loads get small pistol. If all I can find next time are Mag primers I will use them the same way I have the other 2 in pistol loads. The last of my rifle primers are saved for rifle loads.
No matter how many times you do it and nothing happens it only takes something going wrong one time to kill you.