The application is ATF Form 6 — Part I, filed IN TRIPLICATE with the Director, signed and dated and containing the information the form requests. That permit is what § 10.1’s prohibition is waived by, and it is specific to the importation applied for rather than a standing entitlement. Nothing about holding an importer’s license substitutes for it.

Release from customs custody is a separate step with its own conditions, and this is where importers are most often caught short. Goods imported under this section by a licensed importer may be released to that importer ON SHOWING that a permit has been obtained for the importation of the goods to be released. The importer must also submit to Customs a copy of the EXPORT LICENSE authorizing the export of the goods from the exporting country — and where the exporting country does not require an export license, a certification to that effect under penalty of perjury. So the paperwork runs at both ends: a permit from this side, and proof of lawful departure from the other.

A separate route exists for goods whose admissibility is not yet settled. The Director SHALL permit conditional importation of a firearm, firearm barrel, or ammunition for the purpose of examining and testing it in connection with determining whether its importation will be authorized. That application goes on ATF Form 6, filed in duplicate. The Director may impose conditions — including that the goods be shipped directly from customs custody to the Director, and that the importer agree to EXPORT OR DESTROY them if the determination goes against admissibility. Release under a conditional authorization happens on payment of customs duties where applicable, and in the manner the conditional authorization prescribes. So the goods do arrive — released on payment of customs duties where applicable, in the manner the conditional authorization prescribes — but they arrive provisionally. What is conditional is whether they may stay: where the authorization imposed the export-or-destroy undertaking, an adverse determination is what calls it in.