This is Beeron, not Bill,
I was just using his question/answer to reiterate my own.
I know you don't thread them for chokes normally.
but I have and have had several shotgun barrels that were choked as the standard with no threading for removeable chokes.
These are usually IMP CYL in my experience, CYL being more or less a smooth straight tube as I understand it.
IMP CYL being reduced toward the muzzle somewhat.
Before removeable chokes this is more or less the standard right? you bought a shotgun with a certain "Choke" for the game you were hunting, nice tight patterns for quail and more open patterns for geese and ducks?
I had a 20" rem 870 barrel with smooth bore and open sights (not that old) that was IMP CYL and it beat out every other barrel by a significant margin in pattering buck shot.
I think it is safe to assume that these barrels you are offering will all be CYL, especially if they are cut downs of anything longer.
I think I have my answer is what I'm saying.
Beeron, I'm sorry but I assumed you would have read my post and infered that yes, these are a cylinder bore. As I mentioned we sell these first and foremost as a bear defence gun and this means slugs and double ought buck for the most part. You *can use and imp cyl choke for some slugs but our advice is since the guns have a TEN INCH barrel and that pissed off lump of fur and teeth are barrelling down on you at what will seem an ungodly speed you won't exactly have time to group those shots. You will be lucky to remember to switch off the safety and pull the trigger before you become bear poop.
And our barrels are not 'cut downs' ,we make them 100% from scratcch which is the reason per Canadian law that we can make them any length we want. ( ;