I recently bought some small pistol primers for CAS. They were Remington 1 1/2 size. Remington also makes a small pistol size 5 1/2. Upon researching "what the hell's the difference," I found the 1 1/2s are made for lower pressure loads like 38SPL due to the thinner cup. The 5 1/2s were recommended to be used in high pressure loads like 357 mag and even the 9mm to prevent primer cup flow. I've seen multiple shooters who have highly tuned slicked up rifles that will not fire off CCI or Winchester primers but do quite well with Federal small pistol primers. For those who are having trouble finding Federal SP primers it looks like the Remington 1 1/2s may well be a good substitute for the Federals that for a while, were hard to find. Since I own no highly tuned slicked up rifles I have gotten through the primer shortage by using small rifle primers in the 357/38s.
