Interestingly, historically, weapons were one of the longest lead items when ordering and buildings a ship. It’s because the gun barrels for the turrets of larger ships took so long to make reliably, larger guns needed like a year lead to have the barrels needed ready.
Though keep in mind they weren’t just making the 8-12 barrels the ship needed initially, they were making them in batches of a few dozen to replace the barrels as they got worn out.
But this is all under the category of “logistics is a cruel mistress, and the true enemy when waging war.”