Per naval experts, each 16 inch shell cost about $500.
First, let me state, this is not my line of work and I suspect you are intensely familiar with the newer equipment.
Not trolling or trying to prove any points.
The projectile is 2,700 pounds and I don’t know how many hundred pounds of powder are used for each round.
And the barrel life is about 300 rounds $$$
Nothing Mil-Spec that weighs in at ~3,000 pounds ever cost $500?
I recall seeing an unexploded projectile next to the trail in I Corps RVN. HUGE!
The New Jersey and Puff were always a fun hot topic at the time.
I’m assuming the Navy stated cost was in WW2 dollars due to when most of the projectiles were made. Economies of scale when you are cranking out millions of copies of something are pretty impressive.
Gunpowder on the scale that the US Navy was buying it was surprisingly cheap too, even today the government Lake City arsenal often pays well less than $8 per pound, would have been even less back then.
The barrel life of a 16” Naval gun is not 300 rounds. The life of the “lifespan” of the liner is 1,500 rounds. As for the number of rounds that can go through the barrel, that number likely is at least 100,000.