There is hereby imposed upon the sale by the manufacturer, producer, or importer of the following articles a tax equivalent to the specified percent of the price for which so sold:
Articles taxable at 10 percent—
Articles taxable at 11 percent—
Firearms (other than pistols and revolvers).
Shells, and cartridges.
(Aug. 16, 1954, ch. 736, 68A Stat. 490.)