Your brass is US manufacture WWII M2 30/06 brass. The two numbers denotes manufacture date. "DM" is Des Moines ammunition plant and "SL" is the St. Louis plant.
These two ammunition plants operated only during WWII. The original ammunition had chlorate (corrosive) primers.
I've reloaded this type of brass for many years. The primer pocket crimp will need to be removed before re-priming.
A list of U S Military head stamps can be found here if you find any others you don't recognize :
https://en.wikipedia.org/wiki/List_of_military_headstamps