How are shotgun barrels measured?

[mhanna91]

I live in Indiana, and I am having trouble finding a definate answer as to how shotgun barrel lengths are measured. As far as I can tell, most sources say that they are measured from the face of a closed bolt, and 18 inches is the legal limit. Is this correct? Is there any legal literature to support this?

Thanks,
Mark

[kdcgrohl]

http://www.atf.gov/publications/down...-chapter-2.pdf

[Joeywhat]

I do not know if there is any 'legal' writings on how it is measured, however I do know that at least some ATF agents have measured barrel lengths by dropping a dowel into the barrel with a closed bolt and marking it at the muzzle.

I'm not sure if there is a standard there, but I would say doing it as above would be a safe bet. 18" is the legal limit for a 'standard' shotgun and there is plenty of literature to support this.

[mhanna91]

Thank you very much gentlemen, that was the answer I was looking for. Perfect link.

[Glock17JHP]

I really enjoyed that .PDF file... especially the umbrella gun...