Rifling that is not rifling...Lancaster oval bore...

I'm pretty unimpressed with Franklin Armory's reformation.

However, the idea of well it's not "rifling" brought to mind Russian regulations of rifles vs. smooth bores.

In Russia they use an oval bore called a lancaster bore to provide some sort of spin stabilization without "rifling".

What, if any application might a lancaster bore have in relation to US NFA regs?

What might happen if it was determined that it does count as "rifling"? Perhaps shotshell firing handguns may benefit? or not?

What might happen if it was determined not to count as "rifling"? Perhaps it may be a more effective solution to what the reformation is attempting?

TED

It is just a different kind of polygonal rifling. In this case the polygonal equivalent of 2 land rifling.

Wonder if a non-permanently attached muzzle device similar to a paradox choke tube would get a pass and halfway work.