"The way the frame was first assembled into a working firearm would be the proper designation under Federal law."This quote brings another question to mind

I have never bought a Contender new but I would guess that you buy a frame,
and then you pick a barrel you want to go with it.
So if you pick a hand gun barrel it would be registered as such
but if you got a rifle barrel then it would be registered as such
A little extra thrown in

, What if you bought it as a muzzle loader

I bought a frame with out a barrel and am registering as new to me so WHY
would I not be able to register as a handgun?
It does not have a barrel or Caliber even?
I am not questioning your response but think MAYBE you might be able to change it
