Man,

You have jumped into this without doing much of a basic search. You’ve always been able to use EForms as an entity, at least when the system was up. Using it as an individual has only been allowed in the last year and a half or so.

And if you didn’t know to measure with stock extended, you’ve failed to do one of the most basic things...read the instructions on the form, which includes:

Description of Firearm and Markings. (1) Item 4a. If you are modifying an existing firearm, enter the name and location of the original manufacturer. If you are creating the firearm, enter the maker’s name, city and state. (2) Item 4b. The types of NFA firearms are listed in the definitions; (3) Item 4c. Specify one caliber or gauge. If there is another designation, indicate the designation in item 4h. (4) Item 4d. Show the model designation (if known). (5) Item 4e and 4f. Specify one barrel length and overall length in items 4e and 4f as applicable. Note: if the firearm has a folding or collapsible stock, the overall measurement is to be made with the stock extended. (6) Item 4g. Do not alter or modify the serial number of an existing firearm . Enter the existing serial number or, if a newfirearm, one you create. (7) Markings: The maker is required to mark the firearm with the maker’s name, city and state as shown in item 3b. All markings are to be in compliance with 27 CFR 478.92 and 479.102.

...and all this talk about what lengths get approved means nothing. They don’t know what you’re building. The general rule is barrel + 19”. But, you may be running a minimalist stock, or a fixed rifle stock. They have no idea. So there’s no reason to call them and ask what the length should be. Asking the manufacturer at least makes a little sense.