5.56 Fiocchi Range Dynamics 55gr FMJ 50rdsReliable 5. 56 NATO Range Loads Fiocchi Range Dynamics The Fiocchi Range Dynamics 5. 56 NATO 55 Grain FMJ is a dependable, cost effective range load built for high volume AR 15 and MSR shooters who want consistent performance without paying premium prices. Loaded with a 55 grain full metal jacket bullet the standard 5. 56 NATO training and practice projectile these rounds deliver reliable feeding, consistent accuracy, and clean cycling in any 5. 56