When we reference bottle capacity for our wine cellars, we are referring to the maximum quantity of "standard" Bordeaux-size bottles that will fit into that cellar. In reality, as you can see from the chart above, there is no true standard size bottle these days as bottles come in varying styles, sizes and shapes.
Some are extremely tall and thin (like a Riesling bottle), others are shorter yet wide at the shoulders (like the Pinot Noir or Turley bottle) and others are tall, wide and broad at the shoulders (like your large California red bottle).If you have any of these non "standard" Bordeaux size bottles in your collection, your capacity can be lower than what we state the unit can hold.
Here is our rule of thumb: If up to half of your collection consists of non-standard Bordeaux-size bottles, your maximum capacity may be reduced by 20-25%. If your collection consists mostly of these larger sized bottles, your maximum capacity may be reduced by as much as 40%. The one thing we do know is that all collections are different, and that's the great thing about collecting wine!