Actually, it’s more like 55 lbs per 1000 for 7.62 - 32 lbs is about right for 5.56NATO.
That’s just under 10,000 lbs. These guys were breaking the law just by how mach they were transporting and how much they exceeded GVW of the van.
180,000 rounds of 7.62 is a lot of firepower
Plenty enough to wear out an M1A.