including the buyer's info, description/caliber/gauge of weapon, and SERIAL #. How can you tell one fowling piece from another, made by the same "business", without a Ser.#? The lack of mandatory serial #'s surely would have been a tipoff to the Founders against "unregulated" arms, but no action was taken on this until 1968. Therefore, it is my hypothesis, that they didn't care about "registration". They did put "the people" in the 2d Amendment, after all, and I assume that means the same as "the people" in the other amendments, as well. After all, heaven forbid the "militia" couldn't freely assemble, or the "militia" be secure in their persons, houses, papers, and effects, etc. Hope this clears that up.

ETA: Although, a properly "regulated" double barrel shotgun is a beautiful thing. ("Regulated", as the barrels are aligned so both impact the same spot at a certain range. Usually 25-30 yards, IIRC.)