[BrokenPrism]

The only thing i found this:

The typical loadout on a fleet destroyer was about 30 depth charges, while dedicated escort ships had a very large loadout, of as many as 300 depth charges.

I hope I can find a bit more, but we will see... But what i can say with certainty is that 6 charges is way to low. Most destroyers would launch a series of 6 DC, listen for the sub again an repeat. Even in de early stages of the war a destroyer would have enough to make at least 2-3 of these runs before running out.

Edit: It appears that most DC launchers could hold 12 charges at once, with 2 on board most vessels that would be 24 DC, i couldn't find any info on how many additional ones where carried, as well as how many the K- and Y-Launchers had in stock, but i think these would be the captains choice, depending on the task of his vessel...