The second stud under the barrels (the one between the fore-end loop and the action) isn't a second fore-end loop. The screw grip fore-end fastener engages only the front lug as it isn't the kind of mechanism that could engage both. The fore-end loop, which the screw grip lever engages, is soldered to the barrels. This joint sometimes fails under recoil and the fore-end loop comes off. Such failures are normally associated with high volume shooting with double shotguns and usually isn't a problem with heavy double rifles. However, it certainly might be with a BP 8 bore. From the way the second lug fits into the fore-end iron, I believe it to be nothing more than a recoil shoulder to relieve the stress on the fore-end loop. This could be original (I've never seen this before, but I don't pay much attention to BP 8's), or a modification made after such a failure.

As far as the front lump extending through the bottom of the action....just easier to make that way. Some say that a through-lump means that it isn't a best gun. Champlin Firearms currently has a Holland & Holland Royal Deluxe DR that has a through lump, and isn't stocked to the fences either. Go figure.
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