Possible way to modify hangun fire-rate/characteristics? Model?

[Von_Fontlebottom]

This is a bit of a childishly fun idea but I really have found successes with firing into planes engines from below with my pistol. Since none of the guns can rotate to the 90 degree angles possible on some mounts, I thought it would be fun to alter the C96 Mauser's characteristics to at least match the full-auto variant that's mostly a film invention.

 

Is there any way to accomplish this? 

[Todt_Von_Oben]

Well, there actually was a fully-automatic version of the C96 called the M712 Schnellfeuer produced from 1932 to 1938.  I have a CO2-powered version with the selector switch.  Doesn't have much power, and the gas is gone after three short bursts.  Too futuristic for Flying Circus, I'm afraid; but still. it's a lot of fun for target practice.  BRRRRRRP!   😎