Last night I was looking for reloading data on how to closely match NATO spec M193, since my package of 500 Lake City 5.56×45 brass arrived last night. I found some interesting information in my search.  The first is on the history of the powers that were used in the production of M193 round. The second is some background and comparison of the Chinese 5.8x42mm round against other commonly used rounds. Neither of these are new, but I found them interesting, and thought maybe readers would too.