How to Measure the OAL (Overall Length ) of your SBR for your ATF Form 1 Application
We get asked this all the time. What am I supposed write in for the overall length (OAL length) for my SBR that I can't legally build until my tax stamp comes in?
We reached out to the ATF to get an answer to this question. The National Firearms Act Division recommends that you use an estimate for the overall length of the SBR. You can take the measurement of your barrel and add it the length of your lower with your stock and get pretty close to what the SBR overall length would be when it is fully assembled, a.k.a manufactured. Note: The overall length of your SBR is with the stock fully extended and any removable muzzle devices removed.
Once you receive your tax stamp back from the ATF, you can then assemble and manufacture your SBR. After you have completed that you can then measure the true overall length of the SBR. If this measurement of your SBR is different than your estimate that you wrote on your ATF Form 1 application, you will need to submit a change of length letter to the ATF. They will then send back to you an approval letter that you will need to keep with the approved tax stamp.
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