Nearly every snub owner wants to know what the best possible self-defense ammunition is for his snub.  While it is an important question, determining the correct answer is challenging. Every month one shooting magazine or another reports on a new development in snub related self-defense ammunition.  Consequently, with these ever evolving innovations any advice offered today would be obsolete by tomorrow. Additionally if there was available some penultimate self-defense snub ammunition neither I nor any other responsible shooting instructor could give it an unqualified recommend without knowing a little about the shooter. What for example is his skill level? What are his physical limitations if any? What is the age, material and condition of the snub he owns? Even suggesting self-defense ammunition that has been available for years would requires some knowledge of the shooter and his equipment. Rather that offer a specific suggestion I would rather offer two guidelines for the shooter who is looking to determine what ammunition would optimize his personal self-defense snub. When evaluating any self-defense ammunition for use in your snub the first priority is to establish complete reliably. Reliable ammunition in a reliable snub trumps all other consideration as the priority. Only after ammunition reliability has been confirmed can other factors be considered. The second ammunition consideration is A.C.L.U. compatibly (No, not that A.C.L.U.)  Let’s look at both.