Generally speaking, when you double diameter of a tube, the volume goes up by 4X...
Same with a square...
A 2x2 box or a 4x4 box.... 2x2=4..... 4x4=16.....
That's how I came up with the multiplier of 1.5.....
OK, every web site seems to have "conflicting" information.... Let's figure this out...
One site has these numbers....
1 US cup of Pork, fresh, variety meats and by-products, kidneys, cooked, braised weighs 4.93835 ounces [oz] ....
1 cup = 8 fluid ounces = ~237 cubic centimeters ...
There are 25.4 mm per 1 inch...
A 64mm casing.. / 25.4 = ~ 2.52 inches diameter.....
2.52 x 2.52 x 0.7854 x 1 inch in length = 4.987 cubic inches or 82 cc's...
So, ~5 oz. of pork in 237 cc's... and 1" of 64mm casing = 82 cc's....
82/237 = 0.34 x 5 oz. = 1.75 oz. per 1 inch weight of pork in a 64mm casing
1.75 oz./inch x 12 inches = 21 ounces per 12" of casing...
All that being said, I have no idea how these guys come up with their numbers.....
Maybe the number 4.93835 ounces of pork per 1 US cup is meat and no fat or ???.. fat and now meat... Fat weighs a lot less than meat... meat weighs a lot more than fat...
AND, I weigh a lot more now than I weighed when I was 17 years old too....
This just proves you can't figure out much from stuff you find on the World Wide Web..
Seems I just wasted a lot of time... NOT... You can't believe everything you read on the web...