You may struggle on this one. martin Streetly's excellent "Aircraft of 100 Group" doesn't cover this point, and I think if anyone did, he wore are, however, a couple of photos and drawings of the rear .50 cals on the B17s. They have a collar on the end which might be what you seek.
Andrew
Does anyone have a good reference for the flash suppressors used on the .50
> calibre machine guns on the B-24s that flew the night missions out of RAF
> Harrington during WW2? I've searched the Carpetbagger website and I haven't
> found any -- yet. TIA
> Ed
> "'Twas a woman who drove me to drink,
> and I never had the courtesy to thank her for it."
> W. C. Fields
> (Delete text after dot com for e-mail reply.)