I thought that part was a little ridiculous also, but to sidestep "constructive intent" I just researched a build with a similar stock and barrel length and copied their OAL

When turning a pistol into an SBR you would have a pretty good idea of exactly how long it'll be. The summation of the Thompson case was that if you can legally assemble ALL your receivers into legal configurations there's no constructive intent, i.e. if you ONLY have short sub-16" barrels and rifle configured receivers then that'd would clearly be constructive intent since there is no legal configuration that could be made.

Using your example of an AR15, you could measure what you currently have, 16" + plus and subtract however much shorter you want it to be eventually. Keep in mind that it may not be exact, you're supposed to notify the NFA branch of any permanent changes, such as if you sold your 14.5" 5.56 upper that you originally intended to use and used to determine the OAL on your Form1 prior to receiving your approval, but will now be using a 12.5" .300Blk in the future. But after you receive the approval you acquire another sub-16" upper in a different caliber, that'd be legal to use also. With ARs there are technically no "permanent changes" when it comes to caliber or barrel length. That really applies to designs that aren't easily reconfigured within 60 seconds.

OAL for a 16" M4 with the stock fully collapsed is approximately 32":
14.5" = 30.5" OAL
12.5" = 28.5" OAL
11.5" = 27.5" OAL
10.5" = 26.5" OAL
7.5" = 23.5" OAL


Obviously the final configuration will vary depending on the exact stock/buffer tube/exact barrel length ( some companies like CMMG offer odd sizes like 10.3"/14.7" ) , muzzle devices unless permanently attached wouldn't be included.

My understanding (from copious Internet research, lol) is that you measure the OAL with the stock fully extended, not collapsed.

The best logic I've heard is that a collapsible stock is like a folding stock; you collapse or fold it for storage or transportation, but the "usable" configuration is with the stock extended.

Technology has outpaced the 1934 rule book.

I had also read that the oal length measurement was taken with a collapsible stock fully extended

I have yet to see a definitive publication from ATF on this, sO i'm not taking a firm stand either way.

The ATF publications that are available say the " 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."

If the non permanent muzzle device isn't part of the barrel ,or OAL, where's the logic in including the collapsible/easily removeable part of the buttstock part of the OAL? The collapsing buttstock of an AR is a hell of a lot easier/faster to remove then a properly attached flash hider. Following that logic, the rearmost portion of the firearm would be the end of the buffer tube.

I'm inclined to agree with NWRed's logic. It would be nice to know for sure, though.

Honestly I feel its irrelevant to anything that has an easily replaceable stock, what you list isnt what it has to be for eternity. Suppressors cant ever be longer than listed, but with SBRs/SBSs theres no issue with varying lengths, even if permenant.

Its possibly more pertinent to something like a cut down .22 rifle where you wouldnt be changing the stock or barrel lengths, such as the examples in the NFA Guide PDF. The guide doesnt use any modern or modular weapons for examples, strictly hacksaw modified "bubba-gunsmithed" bullshit you'd expect from a 1960's Black Panthers theme'd movie.

If you think of the types and styles of firearms available in '34, and the way in which they were typically handled and fired, the NFA makes a little more sense as far the descriptions. Pistols are only held with 1 hand, "weapons made from rifles/shotguns" doesn't consider that manufacturers would sell stripped receivers for the purpose of building rifle caliber pistols etc.

The "weapons made from" aspect hangs up a lot of people who cant grasp the concept of AOWs made from virgin receivers or PGO models that arent "designed to be shoulder fired" etc.

I completely agree with what you guys are saying here. The comprehensive walkthrough for filling out a form 1 that I used from AR15.com simply stated "OAL is measured with the collapsible stock in the fully extended position." Certainly nothing definitive, but the walkthrough was so well done that I decided to just take this guy at his word.

And on a lighter note, filed my eform 1 today! Wooty woot! SBR here we come!

An update on my two Form 1 SBRs that I submitted earlier in this thread....

PS90: Submitted 12/30/14, approval received 2/9/15, total flow 41 days.
AR-15: Submitted 1/3/15, approval received 2/10/15, total flow 38 days.

Sweet!

So when you say 'approved', does that mean you have the tax stamps in hand, or just an email notification?

My thoughts exactly. Is there printable paperwork in the email or do you have to wait by the mailbox for your fun ticket?

With eforms, all you get is a printed copy of a stamp.

Outstanding, thank you!

Yup. I have printable stamps, I'm good to go. I already PM'd Trevor so I can get the engraving done.