I have two favourites actually, the Suomi M/31 smg and the Degtyarev DP-27 light machinegun, both weapons used by my dad in his army service, just too bad I didn't get chance to use the M/31 as it was phased out of service by that time.
Now I lived up by Biggin Hill RAF Fighter Station during WW2, and I would watch the Spitfires battling away in skies above, that Merlin engine sound is burnt in to my brain and I can still pick out long before I see the plane.[i