Shortest legal barrel for rifle???

[edge]

If your rifle action is used to make a weapon 26 inches OAL with a barrel at least 16 inches AND is designed to be fired from the shoulder then it is a rifle and no fee required.

Folding or collapsible stocks may or may not be allowed.

edge.

Here is something describing made from a rifle and also folding stocks.

http://www.atf.gov/publications/download/p/atf-p-5320-8/atf-p-5320-8-chapter-2.pdf

 

[IdahoCTD]

If you buy a action only then it is undesignated. That means it can be used for a rifle or a pistol build. A rifle action can't be used as a pistol but a pistol action can be used as a rifle. So if you buy a action only and build a long barrel pistol with a removable butt stock then your good. I have a buddy that has several actions he bought just as actions to use for pistols. He was in the same boat and didn't want to get in trouble with the ATF. You pay through the nose to buy them as actions only but it solves your problem.