I recently purchased some brass at a gun show.  The brass is marked either W.R.A.Co - 30 Army, or REM-UMC - 30 USA.  All (except 2) had correct dimensions, although some needed to be trimmed for length.  Most had been reloaded (based on the variance in the primers used). 

Two of the cartridges in the bag were loaded/live however, and this is what is baffling me...  I pulled the bullets and discarded the powder, and I will not use the brass either, but I am curious about these two:  They are approximately 1/8 inch shorter than a normal Krag Case.  Otherwise, the dimensions are correct.  Also, the case heads have been stamped with some kind of pattern.  They were loaded with 150 grain spitzer bullets with what appears to be a nickel jacket.  I have included some pictures of these cases.   

Has anyone encountered cases like these?  Does the 1/8 inch shorter case present a problem in a Krag?  Also, what era is a case marked 30 Army/30 USA from?

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