Hi, as far as I could find in documentation the gun used these fixed rounds:
10,5 cm Sprenggranatpatrone L/4,4
10,5 cm Sprenggranatpatrone L/4,4 (Üb W)
10,5 cm Sprenggranatpatrone L/4,4 (Üb R)
10,5 cm Sprenggranatpatrone L/4,4 (Blind)
10,5 cm Panzergranatpatrone Flak
10,5 cm Panzergranatpatrone Flak (Üb)
the projectiles for these rounds are here:
10,5cm Sprgr L/4,4
10,5cm Sprgr L/4,4 Stg
10,5cm Sprgr L/4,4 Pr.zugz.
10,5cm Sprgr L/4,4 (Üb W)
10,5cm Sprgr L/4,4 Stg (Üb W)
10,5cm Sprgr L/4,4 (Üb R)
10,5cm Sprgr L/4,4 (Bl.)
10,5cm Sprgr L/4,4 Stg (Bl.)
10,5cm Sprgr L/4,4 Pr.zugz. (Bl.)
10,5cm Pzgr. Flak
10,5cm Pzgr. Flak (Üb)
There might be more in general use, but for these I have seen documentation like LDv 4402/6 and HDv 481/561.
And there will be a lot of experimentals.
Bob