Ok, so It's discovered. Its propably only during while these event items are out, so I will describe how to buy shrapnel(Atleast on my server).
No fiddler or any other program than a browser is required.
1. Log in on your account.
2. Log onto the seachart.
3. Go to settings, graphics and put viewport size to 640 x 480.
4. Wait until the windows have refreshed.
5. Go to where you buy ammunition from the Seachart.
6. And click on the shrapnel icon and buy all you can afford.
I can't guarantee that this is safe though.