Well, duh, we tax the guns.
The $200 tax in 1934 was punitive, 80% the price of a Thompson, intended to discourage ownership.
So to keep the bookkeeping simple, we include a 100% tax for recordkeeping on all "assault weapons," or just all guns. If that isn't enough, we increase it.
And offload a lot of the work to call centers and data entry contractors abroad.