With all the stockpiling discussions, I've gone out looking for some more ammunition to stash. I believe that XM193 is basically the same as M193 but it failed some portion of the Military Specification. From what I've read this ammunition is fine in our civilian/LE environment.
Tonight I was looking at the offerings of several vendors who had XM193A, XM193B, and XM193C. All made the same claims concerning its being manufactured by Federal for the Gov, however, some small detail kept if from being accepted. My being somewhat simpleminded does not help in my understanding of the suffix lettering. Typically a suffix on ammunition denotes an improvement or design change of some sort.
Will some kind sole clue me in as to what the suffix meanings on XM193 mean.
NAVMC 2667 MARINE CORPS DESK TOP DICTIONARY (LOGISTICS) (1984 EDITION) TRAINING USE ONLY IS DEFINED AS AN AMMUNITION ITEM WHICH FUNCTIONS IN A MANNER CONTRARY TO ITS INTENDED DESIGN WITHOUT CONSTITUTING A HAZARD TO PERSONNEL AND/OR EQUIPMENT WHEN USED IN ACCORDANCE WITH SPECIFIED LIMITATIONS.And then there is this excerpt from Field Manual 23-65, Section 1-7.f, "Precautions" (1): Do not fire small-arms ammunition graded and marked "For Training Use Only" over the heads of troops.
Per senior USMC NCO PD means pulldown ie, ammo produced from components from ammunition pulled down for not meeting milspec in some way. Ammo will ususally have a X modifier in front of the M and series number. [XM193 etc].
Per ATK (run Lake City & Radford Ammo Plants- Alliant Techsevervices) XM designates contract over run ammunition that may or may not meet all relevant military specifications.
..................... I'm not aware of any service specific suffix meanings with respect to M193 ammunition (For example M118LR ammo was optimized for Long Range work with a different bullet & powder charge and was previously marked SB for Special Ball). The various suffixes you mention might designate lots of ammo or source of the ball (bullet).