wow i learned a lot about guns in japan that i cant find in youtube... now what i want to know if this half riffling is a japan thing or other country use it and in terms of performance is half riffling weaker than a normal riffling?..
@zetsuravez Half rifling is just as effective as a fully rifled barrel. The reason why slug barrels in japan are half rifled is because a fully rifled shotgun in japan is considered a rifle instead of a shotgun. And since a fully rifled shotgun exceeds the legal bore size limit of rifles in japan they only rifle the barrel halfway to sidestep that law.
@zetsuravez
In America, it can be dicey depending on the state since you have federal firearm laws and 50 different state laws for everything. In California, which is probably the last fucking state you'd want to live in if you want something more dangerous than a spork (and it damn well better be made of recycled materials), there is no such thing as a "rifled shotgun" unless you want be anally violated in prison for the next decade or so, since California stipulates that shotguns must have smoothbores and anything that is rifled is a rifle... and 12GA shotguns are .51, which violates their .50 ban... thing. So even if you are shooting birdshot through a rifled barrel, they consider it the same as shooting a .50 BMG anti-materiel rifle.