Do You Have An Illegal SBR? Measure Your Gun! – The Legal Brief ~ VIDEO

The Gun Collective
The Gun Collective

USA – -( Welcome back to The Legal Brief, the show where we CRUSH the various legal myths and misinformation surrounding various areas of the gun world. I’m your host Adam Kraut and today we’re talking determining your barrel length and your guns overall length.

Some of you watching may be asking, why would I ever need to determine my barrel length or overall length? As you may remember from the recent videos on Short Barrel Rifles and Short Barrel Shotguns, barrel length and overall length are the criteria for being classified as a SBR or SBS.. If you missed those episodes or are not sure what I am talking about, be sure to check out the rest of The Legal Brief episodes here on The Gun Collective.

So how does one measure the length of a barrel? The ATF procedure to measure the length of a barrel is to measure from the closed bolt or breech face to the furthest end of the barrel or permanently attached muzzle device. But Adam, you said we were talking about measuring the barrel, why does ATF’s procedure include measuring a permanently attached muzzle device?

ATF considers a muzzle device that has been permanently attached to be part of the barrel and therefore counts towards the length. Ways to permanently attach a muzzle device include full fusion gas or electric steel-seam welding, high temperature silver solder (1100 degrees) or blind pinning and welding over the pin head. If your muzzle device is not permanently attached using one of those methods, you must remove it in order to properly determine the length of the barrel.

After you’ve determined whether your muzzle device is permanently attached or removed it from the barrel, the next step is to locate some sort of dowel or rod. A wooden one works just fine. Drop the dowel or rod into the barrel until it touches the bolt or breech face, which has to be closed. Mark the outside of the rod at the end of the muzzle crown (if you don’t have a permanently attached muzzle device) or at the end of the muzzle device if it is permanently attached. Remove the rod and measure from the mark to the end of the rod. That is your barrel length, remember this is very techincal stuff we’re talking about here.

Remember, if the barrel length is less than 16 inches, it is possible that the firearm could be a short barrel rifle (if you are building a rifle or it is already on a rifle) and if the barrel length is less than 18 inches, it is possible the firearm could be a short barrel shotgun (again if you are building a shotgun or it is already a shotgun). Both of these firearms would be subject to the purview of the National Firearms Act and would require the firearm to be registered accordingly. Keep your eyes peeled for a video on how to fill out a Form 1 in the future.

The overall length of your rifle or shotgun may also classify it as a Short Barrel Rifle or Short Barrel Shotgun. So how is the overall length determined? Once again we turn to ATF’s procedure on measuring overall length. The overall length of a firearm is the distance between the muzzle of the barrel and the rearmost portion of the weapon measured on a line parallel to the axis of the bore. Seems simple enough right? Two things to bear in mind when determining the overall length of your rifle or shotgun. First, if the rifle has a permanently attached muzzle device, that is part of the overall length. Second, if the rifle or shotgun has a collapsable stock, the overall length is measured with the stock extended. The stock extended is a departure from how some states require individuals to measure the overall length of the firearm. That said, we are discussing federal law, but be aware of the difference if you happen to reside in one of those states.

Don’t forget, if you determine the overall length of either your shotgun or rifle to be less than 26 inches it is either a short barrel shotgun or short barrel rifle under federal law. Once again, as with the barrel length, if this is the case, the firearm is a NFA firearm and must be registered.

If in either instance you have a gun that falls under the NFA but is not registered you are violating federal law and the penalties associated with violations are only about $10,000 and 10 years of imprisonment or both, if the maximum penalties are levied against you along with the firearm being subject to forfeiture. In other words, don’t have possession of unregistered short barrel shotguns or short barrel rifles.

Size Matters SBR
Do You Have An Illegal SBR? Measure Your Gun! – The Legal Brief ~ VIDEO

Hopefully that explains the proper way to determine your barrel length and firearms overall length. If you guys liked this episode, you know what to do, hit that like button and share it around with your friends. Have a question you want answered on this show, head over to The Legal Brief section on Be sure to check out my website for more information on my quest to serve YOU on the NRA Board of Directors. Don’t forget to like The Gun Collective on Facebook, Instagram, YouTube, Full 30, Snap Chat and wherever else you can catch us on social media.

And as always thanks for watching!

Links for this episode:

  • ATF Method for Measuring Barrel Length and Overall Length – Pages 5, 6 and 7 :
  • Firearm – 26 USC § 5845 :
  • Firearm – 27 CFR § 479.11 :
  • Short Barrel Rifle – 18 USC § 921(a)(8) :
  • Short Barrel Rifle – 27 CFR § 478.11 :
  • Short Barrel Shotgun – 18 USC § 921(a)(6) :
  • Short Barrel Shotgun – 27 CFR § 478.11 :

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John B Thayer

What if you live in a “sanctuary city”?
NYC hands out free I.D. cards to illegal immigrants.
Why not for illegal guns?

Gene Ralno

Woe be to the uninformed heir of an illegal firearm. I suppose the leftists believe this is what the founders intended with their 27 straightforward words.


prob this ar can be built to anything, there no mods needed, on fame there nothing to say what u building into, in fack dont madder, this what i dont get u have ar pistol and riffle but u cant have parts to make a sbr . ummmm what am i missing . guns to come apart. atf if u ask there lawyers to tell u word for word what law says u get hug up on, and reason for this they trying redefine what sbr is and drop everything after the or, i have two sbr and lets be… Read more »


What about folding stocks? Should they be measured folded open or closed? How does that impact the OAL. According to the ATF earlier this year, the stock should be folded for measurements, would that not be the same for collapsible stocks? Measure them closed and not extended?

Steve McNamara

This article is not accurate. If your barrel is under 16” and the overall length is under 26” it does NOT automatically mean you have an SBR and if its not registered you are violating federal law. The auther is missing a very important factor. The butstock. If the weapon has a brace instead of a butstock it is a pistol and does NOT need an nfa tax stamp. You can not put a vertical foregrip on the pistol. It must be angled. The atf defines a rifle as having a butstick which is intended to be fired from the… Read more »


A pistol grip shotgun with a barrel at least 18.5 inches. The barrel was cut down to that length. This is legal I assume. (?)

Someone recently told me that if the barrel was originally longer but was modified to lengths still within legal limits, i.e., 18.5 in. +, the gun is now illegal because it was “modified.”

Can anyone resolve this for me?

Patrick Gonzalez

What is the correct Form to Change My AK Pistol to an SBR By My self Legally?
And is there Less than 26 inches is classified as A SBR Is there a minimum length ?
For example My century Arm C39 has a 11 1/2 inch barrel Maybe with a custom M4 tube and stock get it around 30 inches extended.
Or if I use a Micro Draco with about a 5 1/2 inch barrel and custom fixed stock get it under 24 inches total Length .

Patrick Gonzalez

Thanks for the help but you don’t understand my question. After I fill out the proper to make an SBR and receive it approved ! I want to make my AK pistol a SBR . And want to find out is there a minimum length .
And proper form..
Still looking in to it.

Thank you


you do NOT have to register your draco pistol. it is exactly that.. a pistol. This article is misleading and false! Perhaps the original article is old but do NOT go registering your weapons based on this inaccurate information. This page should be updated to inform ppl correctly

Parker Elrod

If the rifle in question meets the overall length requirement but doesn’t meet the barrel length requirement is it illegal?


“If in either instance you have a gun that falls under the NFA but is not registered you are violating federal law…”

Either instance, to me, means it must meet BOTH barrel length AND overall length.

Jim in Conroe

Either means one or the other as in “either the overall length is less than the required minimum or the barrel is shorter than the required minimum.

That One Guy


the rifle must be at least 26″ in overall length, AND the barrel must be at least 16″ in length.

if your rifle falls short in either measurment, it’s an SBR.


Thanks for the information. All of these infringements on the 2nd Amendment will send a person to jail for a technicality that has not harmed anyone. How does the barrel length regulation cause personal harm to anyone, other than the person that the BATF etc. wants to arrest, for a shorter barrel vs no arrest for a longer barrel? Sounds like a no victim crime, except for the person with the barrel that comes up short on the measuring tape becoming the victim. Maybe the BATF thinks having the shorter barrel will automatically create a criminal act from the owners?… Read more »


How can that possibly be when I can always unhook the lower, which is the actual weapon by these very law(s), and what I would have left in my hand or on the table is possibly just a toy as it is not a rifle or a gun without any lower mechanism and I could put a orange tip on the end of it to identify it as a toy.

Jim in

What constitutes the firearm is defined in the law, and just taking it apart does not change the length of the barrel for purposes of determining if it is an SBR. You could always argue the point, but I wouldn’t take that bet.


It is considered “constructive posession” unless you have on hand the parts to make a legal configuration. So if you have an AR upper with a 10″ barrel, but no completed lower that is classified as a “pistol”, then you are in constructive posession of an illegal SBR (assuming you don’t have a registered SBR lower).


You’re full of it. It’s not illegal to own just a short barrel or an Upper part of let’s say an AR. You can even Legally buy completed Uppers with barrels in 10.5, 7.5 inches, etc Online. They cannot charge you with constructive possession because who’s to say it’s not for a Pistol build. Maybe you’re in one of those states like California or New york. Just because you have an upper with a short barrel, it doesn’t immediately mean your building an SBR. Ever heard of AR or AK “pistols”? So with your reasoning, everyone that owns one of… Read more »


You can own the parts you describe but only in your home. if you venture out with the assembled parts to make a SBR but not the parts to make a pistol or federally legit rifle , then bye- b ,your ass is in prison. Sorry if you disagree but that’s the way they see it and their opinion is the only one that counts in court.


You can own the parts you describe but only in your home. if you venture out with the assembled parts to make a SBR but not the parts to make a pistol or federally legit rifle , then bye- b ,your ass is in prison. Sorry if you disagree but that’s the way they see it and their opinion is the only one that counts in court. P.S….not from an opinion from actual events of an associate

Jim in Conroe

Thanks for the article. I immediately went and measured the barrel on the new build I just completed. Whew. I am legal.


What about a gun built exclusively for use on my ranch? It never leaves my property and is never sold to anyone for public use? Can I build an sbr without having to inform the atf?


Jim in Conroe

The probability is that no authority will ever come across your gun, so you are OK on that basis. However, if they do, you will be in violation of the law. This could occur if, for example, you have a fire on your ranch and the police show up with the FD, or if there is an injury that requires EMT assistance and the police show up. In either case of course, they would have to “come across” the gun, but if it gets burned up in a fire and ends up being part of the investigation, you could be… Read more »


When measuring overall length, note that for most long guns the “rearmost portion of the firearm” is below the “line parallel to the bore.” Measuring from the muzzle diagonally to the rearmost point is a bit longer than the way the Feds do it.

Brian McDaniel

This article is informative but does not clearly differentiate that rifle based systems that are not shoulderable don’t fall under the same classification or qualification as an SBR. Example an AR 15 platform with a short barrel and pistol buffer tube.
I realize some may say I’m describing a completely different item, after all “pistol” is in the name of an AR 15 pistol but the article completely ignored the legal existence of short barreled pistols and leads the readers to believe the only qualification they need to concern themselves with is barrel length.