In its current state, the M195 is a effectively an unmodified M61 Vulcan capable of firing 4,000 - 6,000 rpm and with 2100 rounds.
In actuality, it was substantial modified to fire at 750 rpm with a 950 round magazine to allow it to be fired from a helicopter.
Here is a website made by and about some of those who operated the weapon and vehicle. While dated, it contains invaluable information.
Also a video, while made in response to Warthunder's issues it has information relevant to the weapon as a whole.