Lbs of cherries per gallon of wash?

[Norwest]

Hi,

I am heading out to pick cherries at a local U-pick farm to make some Kirch/cherry brandy and am wondering how much to pick. Idealy I would like to make enough to fill my 30 gallon fermenter as this is my only open top fermenter. I also have 15 gallon fermenters but they only have bung holes and will be difficult to use with a viscous mash. I am thinking around 100 lbs but do not have a good conversion to figure out how much volume of fermentable mash it will make. I have 50 lbs of sugar on hand if need be but would rather be a "purist" and use all fruit.

Thanks,

Norwest