TM 9-1005-298-12 Helicopter Machinegun Maintenance is a PDF that I doubt any of us will ever need, it the installation and maintenance manual for a 7.62 minigun used on a OH-6A helicopter.
Its pretty high speed, and if anyone had the resources to buy either the gun or the helicopter then I am sure they would have an armorer and a maintenance guy that already had access to these manuals.
It reminds me of the plane collector that had 6 Browning .50 cal machine guns mounted on his P-51 just because he could. AS the author of the article linked to said “If being a gun collector is a sickness, being an airplane collector is a disease. If you met a guy who spent a million dollars on a gun collection, he’d have a pretty serious collection. The same money wouldn’t even buy half of a P-51. Not to mention the fact that hourly operating costs are in excess of several thousand dollars per hour.”
This 2 DVD set contains over 7 Gigs of US and foreign military manuals and documents including courses, technical and field weapon manuals, training aids, special operations manuals, Army regs, and much more.
This 2 DVD set is $10 with free shipping.