After some digging, I was able to find that post above.
http://mossbergowners.com/forum/ind...shockwave-in-tactical-gear.18687/#post-262817
I'm trying to make sure the right info is there and in context. And if you notice the examples that I used, the Thompson and the XO26 both have RIFLED barrels. The shockwave has a smoothbore and that's where I got into trouble with my reply. And for that, I'll say I was wrong.
Granted there is no reason for me to defend putting out info that's not good. I pride myself in sticking straight with whatever the book has.
I do remember the franklin armory xo-26 that was referenced in your reply. And I also see the post date of Nov 17, 2018 from djcala.
At the time that was posted, ATF didn't care about it because franklinarmory was marketing the xo-26 and reformation models as a firearm designed to be fired using two hands (and as firearms). The ATF has since changed their stance (flip-flopped) again about a year after I had posted that reply.
BREAKING: ATF Declares the Franklin Armory Reformation a GCA/SBS Shotgun, Halts All Retail Sales
December 19, 2019
https://www.thetruthaboutguns.com/b...eformation-a-gca-sbs-shotgun-halts-all-sales/
-------------------------------
So, for at least the time that I had written the post you referenced above, the info was not correct that the end user could add a grip, but if starting from a raw receiver built and sold from the ground up, was occuring, was legal for a time. At that time of the post.
This is where ATF screws a lot of people with their damn retroactive determinations. At the end of the day, ATF should make no determinations at all since they are not congress and should not be making any kind of laws or regulations, but until that changes, it's the world we live in.
I was looking while searching for the above post, and appears that I had also replied to another question you had asked a month later that was really specific that your shockwave fit a very narrow description and that changes would likely put you into legal peril.
-----------------------------------------
http://mossbergowners.com/forum/index.php?threads/tax-stamp-questions.20168/#post-282778
--------------------------------
And a bunch of other replies concerning AOW
http://mossbergowners.com/forum/ind...discussion-about-legallity.17719/#post-249039