27 C.F.R. § 19.517 Gauge for tax determination.
Title 27 - Alcohol, Tobacco Products and Firearms
(a) Packages. When spirits in packages are to be withdrawn from bonded premises on determination of tax on the basis of an individual package gauge, each package shall be gauged unless the tax is to be determined on the production or filling gauge. When packages are gauged, the proprietor shall prepare a package gauge record, according to §19.769, and attach it to the record of tax determination prescribed in §19.761. (b) Tanks. Spirits in tanks which are to be withdrawn on determination of tax shall be gauged (by weighing and proofing) as prescribed in §19.93, and the elements of the gauge shall be recorded on the record of tax determination or on a separate record of the gauge for attachment to the record of tax determination. (c) Cases. Cases of distilled spirits to be withdrawn from bonded premises shall be tax determined on the basis of the contents thereof. The proof gallonage contained in cases shall be determined in accordance with 27 CFR part 30 and the method prescribed in §19.722. (Sec. 201, Pub. L. 85–859, 72 Stat. 1358 (26 U.S.C. 5204); sec. 807, Pub. L. 96–39, 93 Stat. 285 (26 U.S.C. 5213))
Title 27: Alcohol, Tobacco and Firearms
PART 19—DISTILLED SPIRITS PLANTS
Subpart P—Transfer and Withdrawals
Withdrawals on Determination and Payment of Tax
§ 19.517 Gauge for tax determination.

