I made mini mod to improve (in my opinion) the M85 gun on the M60a1 tank, decided to post it in case anyone wanted to use it too.
What it does is double the rate of fire to something closer to reality, changed the sound to the M2hb sound, changed the shots per sound to 6 (sound plays on every sixth shot so it won't overlap but 5/6 shots won't play sound if you're just tapping the fire button), added a tiny notch of dispersion, gave it a 100 round belt (don't know if realistic but more dakka is always fun) and gave .50 AP and ball the heavy ricochet modifier so it kicks up plumes of dust and sparks.
http://www.mediafire.com/?2b0s002trt9bz23You might want kurdes' mini mod that changes the M85 to .50 AP bullets, .50 AP is almost identical to Ball since beta 5 except it's slightly heavier and slightly better against armor.
http://www.mediafire.com/?12vneiwd48vd5db