Fun facts:

The shells reached altitudes of over 130,000 ft, a record for man made projectiles then.

Each shell weighed 234lb., but only 15lb. of that was the explosive payload. All the weight had to go into reinforcing the shell to survive the force of the firing. The resulting explosion was extremely small for a shell of that size, producing craters of only 12ft wide and 4ft deep.

Firings caused such wear on the barrel, that they only lasted 65 shots before the entire barrel had to be shipped back to recast the internal rifling. The wear was so great, that the shells were put into sequential order from 1-65, each shell being slightly thicker than the last to accommodate for the increased width of the barrel as each individual shell wore away the interior. One shell exploded inside the barrel when it was fired out of order.