Problem with custom gunpod

[CptHrki]

So I downloaded the Soviet vertical pack to get the files for the UPK-23 gunpod because it wasn't included in the MiG pack and some of these planes can mount it. I was able to make it attachable to the inner left and right wing stations on the MiG-21MF (lights up the sky) and everything works perfectly, except the shells from these gunpods are coming out with a muzzle velocity about two or three times higher than the internal gun (and they're all the exact same cannon - GSh-23, using the same gun files. I have a few thoughts about why this could be, but I just have no idea what to do to try and fix this.

 

As a side question, is it possible to modify the tracer loading for this gunpod (because I don't see it anywhere in its files)?

 

Moreover, I installed some random Soviet comms to replace windloop.wav on the MiG-21MF, but for some reason the audio is sped up massively (the whole several minute recording loops in like 15 seconds). 

[CptHrki]

Update: I solved the latter two problems, but the velocity is still bugging me...