My grandfather also served in the Russian Army (they lived in Warsaw)  in that war. I was told I'd have to know the regiment or whatever division, so for me it was hopeless.  Sorry!
If you find out anything, let us know.

Isabel Cymerman
Searching:   CUKIERMAN, GRYNBERG, GRYNFARB, LUBELCZYK, ZABAWNY - Siedlce
                   DRONZNIK, NEMENCHINSKI, SAPOZHNIK, SOLECZNIK/SOLC, TABACZNIK - Vilna
                    CYMERMAN, KHELEMSKI, LANSKI, WYSZINSKI, ZYSKIND - Przedborz