Official ATF barrel-measuring tool

[cpileri]

Where can I get the exact same tool(s) used by the ATF to measure barrel lengths?

I know its a metal (not easily deformed so length is constant) rod that slides down the muzzle to the closed breech, no cartridge chambered.

I figure it must be marked in some way at the 16 and/or 18 inch mark, and must be bore sized (ooooo, I need a whole SET of these! ) or have bore-diameter bushings so as to be right along the bore axis. Otherwise t would measure falsely long for going on a slant down the bore.

I've never seen one, and dont know exactly what they might be called so I can't look them up at Brownell's or something.

I just think they would be neat to have, as well as to put down or confirm any doubts that your 'exactly 18-inch' shotgun barrel isn't 17.9" when the ATF or whoever measures it.

Happy 4th!
C-

 

[Fletchette]

I have no idea what they use, but that is irrelevant. All the laws simple state <blank> inches for the length in question. just get a good ruler and add a 1/4 inch for good measure.

If a pissing match were ever to occur, ultimately the buck stops at the National Institute of Standards and Technology (NIST). They use different methods for measuring depending on what accuracy level is required (down to the number of wavelengths of cesium, etc). For more 'normal' accuracies, they have a steel ruler kept in a temperature controlled vault. The ATF's ruler would have to defer to this ruler.

 

[HankB]

I've heard a few people have gotten burned over the method used to measure the barrel.

It's my understanding that you measure from the muzzle to the breach face when the action is closed . . . I've heard that some folks with pump or semi-auto shotguns have gotten into hot water because they measured the overall length of the *detached* barrel, which often has an extension that, in the assembled firearm, goes beyond the breech face.

 

[TarpleyG]

Go buy yourself a 3/16" dowel rod and a Sharpie and go to town...

Greg

 

[cpileri]

dowel and sharpie

Well, that's the way we all do it right now if we're so inclined:
even check it against a metal ruler for accuracy and consistency, sure.

But I am not asking for alternate methods of measuring the barrel.

I am looking for the REAL tool used (excepting the cesium wavelength device), or even the name of it, or a picture of it, or a description of it- anything!

And if it is some kind of commercially produced kit, i am looking into buying it.

C-

 

[JohnBT]

The exact tool? I have no idea.

A cleaning rod, a piece of tape(or your thumbnail) and a tape measure will work. John

 

[Strings]

Silly question, but have you considered just calling Agent Schmuckatelli at your local ATF office? Don't know about where you're at, but the ones at my local office are willing to answer any gun-law question I've ever had, AND admit if they have no idea what I'm talking about...

 

[taliv]

(ooooo, I need a whole SET of these! )

Go buy yourself a 3/16" dowel rod and a Sharpie and go to town...

you mean a whole set of dowel rods... don't forget your 7/16" dowel rod for that sawed-off 50 BMG!

 

[spartacus2002]

have you considered just calling Agent Schmuckatelli at your local ATF office?

Make sure you do so from a pay phone, or from the house of someone you hate

 

[pete f]

I have called the ATFE a couple of dozen times and have not once found the people who answer the phone to be anything but helpful and willing to search out answers to questions that the do not readily have the information to. I know this is counter to the fully accepted position by many that the ATFE is nothing but JBT's but to me, they have been really decent people. And yes, I have asked some iffy questions. as in can a SBR top end be switched from lower to lower? and never gotten anything but nice courteous answers.

 

[slowworm]

PeteF,

I've dealt with my field office a few times as well and had nothing but good results. Heck, they even call me back if they have to research the answer!

Hank has the right answer on this. Just use a cleaning rod and a tape measure to measure the length to the breech with the bolt closed. I add a 1/4" to account for any trimming and measuring errors I may make to keep it just over 16" or 18" for shotgun for my own peace of mind and to account for a possible "short" BATF ruler.