I hadn't caught that... I guess I wasn't paying enough attention. I'd say its remotely possible but not likely. The largest bore NE rifle I've ever seen - that had rifling in it (as opposed to bored out and smooth) is about .65 caliber. Its just about right to take "16 to the pound" musket balls. It is a half-stock by Maynard with horse head patch box in a completely conventional "rifle-style." All of the other NE rifles I've owned or seen have been about .53 to .58 caliber.
I'll add that the heavy barrel "fowler-like" guns I've seen have all had smooth barrels. I once had another Maynard with a pronounced "Roman Nose" butt and a heavy barrel of about .54 caliber. I also remember one that looked superficially like a rifle but utilized a smooth octagon-to-round barrel of almost 1" bore! We generally referred to them as "buck and ball" guns though that is probably a collector term and not a contemporary one.
The basic fact is that no one, myself included, has ever done a really comprehensive study of the NE rifle. Although not as sought after in the collector world, they are quite a bit more rare than "Pennsylvania/Kentucky-style" rifles so assembling enough of them to study in a productive way is a good deal more difficult. There is (or was) such a collection, the owner of which was planning a book but if he's still with us, I imagine he's now too old to bring that project to completion.
