My dad just shot a bull bison, I think the multiplier was 60% of the animal when it was just meat and bones, no skin, cape, or head/skull.

I think his bull weighed close to 1200lbs with no hide or skull.

I think he got 450lbs off a pretty big bull, of pure meat.

I'm thinking a 750lb cow might yeild 250lbs of meat, maybe less. Their hide is awefully thick/full heavy, they have big bones, big skulls.