Hi Peter
I'll look up later and see if I can find anything. Got a couple of books showing interior photos of Lancs. I imagine there would have been some sort of collection bags arrangement. Like you say, I can't think they'd want the empties clanging around on the outside of the a/c, nor rolling around loose inside.
Having said that, from what I've read I don't suppose the front turrets were over-used anyway. You might find they were used more for ground-strafing than air-to-air combat.
Cheers
Ian
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