The 10ML is advertised as using smokeless powder. Looking over the document I stuck above, it looks like anything that can be changed to a regular rifle with a barrel change (listed are things like the Contender and 870), are 4473'd. Also, it appears to be anything built on a firearm reciever (I don't know for sure, but is the 10ML built on the same reciever as a Savage 110?). In addition, it says 'blackpowder substitute', which to me, means Pyrodex, not smokeless.
But I am not a lawyer, that is just my take after reading this.