Yes, correct. It was not always that way.
BUT, as people used a loophole, the loop hole got closed via rulings.
So now it's a possession issue of ammo and launcher with the 37mm
yet the 40mm needs registered anytime, since commerical anti-personnel rounds were made for it intentionally.
the 37mm did not have anti-personell rounds made for it, they got fabricated.
The 40mm do. you have to register them as DD, just as you would have to register a SOSG. Just takes money.
the 37mm does not , as commercial anti-personnel rounds have to be commercially made for it to classify it that way.