Interdimensional Corny Keg ?

I'm fitting out a Igloo ColdMax 100 Quart cooler to take a Corny Keg on the road. As I was playing with the interior dimensions of the cooler (31.5inx13.5inx11in[LxWxH]), giving me 81 quarts of useable volume.

Wanting to know the total volume occupied by the Corny, I plugged in common dimensions:

23"x9"dia

4.5^2*23 = 8 quarts = 4 gallons

Yet the specs on the Corny call it 5 gal capacity.

If the outside of the keg occupies only 4 gallons of volume, but the inside of the keg can hold 5 gallons of volume, is there an interdimensional component to the keg?

I've checked it over a few times. Did I make a mistake somewhere?

You forgot to use pi in your calculations. Also, 8 quarts is only 2 gallons. You're goofed in a couple ways.


Volume of Cylinder = pi (r^2) x length

Volume = pi (4.5in^2) x 23in

Volume = 1463 In^3 / (231 in^3 /Gallon)

Volume = 6.33 gallons

3.14159*4.5^2*23 = 1463.2 cubic inches.

1463.2 cubic inches is 6.3342 US liquid gallons.

But I think 23" is the height of the keg including the handles, so the actual volume is smaller than 23".

Your first error is thinking that 8 quarts = 4 gallons.

Using an online calculator for a tube 9" in diameter by 23" yields a capacity of 6.33 gallons.

ThatGeekGuy said:

Using an online calculator for a tube 9" in diameter by 23" yields a capacity of 6.33 gallons.

Click to expand...

No cheating allowed.

Also, the bottom of the corny is rounded so it's not a perfect cylinder. Calculating the volume of a partial sphere is beyond me, though.

JonM said:

Also, the bottom of the corny is rounded so it's not a perfect cylinder. Calculating the volume of a partial sphere is beyond me, though.

Click to expand...

Well, that's easy.

1) Fill keg with water
2) Pour out contents and measure

LandoLincoln said:

Well, that's easy.

1) Fill keg with water
2) Pour out contents and measure

Click to expand...

Weigh empty. Fill, weigh full.

Elegant in its simplicity.