The DP24 won't fix this issue. You would need a bigger punch trust me.
The DC-15A does 49 damage a shot with an RPM of 250.
The DP-24 does 23 damage with an RPM of 668.
It takes two shots for the DP-24 to do (close) to the same damage as the DC-15A. Which effectively means 1 bullet of the DC15A is 2 bullets of the DP-24.
With that being said, the DP24 has bad bloom and poor hit registration on Gmod. The DC15A would be a general better use weapon than the DP24.
Everyone deals with the same weapon issues as you.
Also, Don't your lore characters get seperate loadouts? Why give them the DP24 if they already have a kit?
+1 for unique sub-unit weapons,
but not this, it won't fix your issue.
-1