moving ammo...

[Krusty]

Not quite... Maybe you're thinking of the ammo tins on vehicle-mounted 50cals we have today. If so they are not the same.

These are for the cheek guns on a B-17G:
http://media.photobucket.com/image/b17%20walkaround/Spodeley/Planes/B17_Bombardier.jpg

Here's an example of the box mount for a waist gun:
http://3.bp.blogspot.com/_zu-DKjmLnoA/Simh3wMcI0I/AAAAAAAAEeI/GLbdN8LotGo/s400/b+17+waist+gun.jpg

Time consuming, definitely. On a 10-hour flight you have lots of time though. How practical is it, though? You cannot get to the B17G chin turret ammo boxes. The tail gun boxes have several long feet of ammo feed belts (and if you use up the ammo past that point, good luck feeding it back!)

The best candidates were the ones with room around them to work -- hypothetically you could plop down an ammo box, disconnect the belt feed and just operate the gun off the new source.

In the dorsal turret it is mightily cramped. Same for ball and tail.

[MarineUS]

I love it when i run out of ammo while bombing .  you get to sit at your computer yelling "GET SOME, GET SOME" till the gf wakes up and tells you to shut up. 

 
Been there.

[LLogann]

Some turret positions cannot be entered from the fuselage, so regardless of whether the ammo can be moved..............   

What about the waist gunners, top and ball turrets?
Since thous are next to each other it can't be that hard to move the ammo, right?

[Vudu15]

If it was me Id knock those feed lines off the gun Im sure they come off and feed the ammo like normal you'd have more loadin time then shootin but youd still be shootin.

[Chauncy]

Personally, it was either possible or not possible.  Simple as that, I am sure there is a source that says yes or no.  I read above an account of somebody replenishing the tail gun.  So, make it like the reload pad.  ".xferammo 200 5 4"  (Transfer 200 rounds from position 5 to position 4)  or whatever ammount was contained in a box.  If the source position had fewer rounds than a set ammount then it could not be done.  Also, when I said make it like the reload pad, make the gunners unavailable for like 1 minute or whatever.  So that way, yes you get ammo, but you gonna pay for it if you get bounced.