I disagreed with him and said it was felony to convert any firearm into full auto unless the appropriate stamp was obtained from the govt......
Was I correct?
You are correct; additionally, possessing a firearm that you can convert by 'turning a screw' (lol) is known as 'constructive possession of a fully-automatic firearm', meaning that it is considered full auto no matter the position of the screw; and finally, your friend is 100% full of shit, because full-auto shotguns are very difficult for legitimate gunmakers and the firearms industry to make. Lots of research, lots of technology, lots of effort, and only a few full-auto shotguns have ever been made.
Was I correct?
You're probably right. There are all manner of homemade silencers and/or methods, each of which is going to get the attention of ATF if you don't have the stamp (can you even get a stamp for a plastic soda bottle?) LOL
More likely, there's something more to the story of being able to convert by merely turning a screw. A shottie like that is probably going to get its own attention by the ATF since they frown on anything that would make a full auto conversion that easy (or even somewhat easy).
Considering the types of things they've cracked down on in the past...things you used to be able to buy but then they started going after the sellers (suppressor kits, ahem, I mean, solvent trap kits, or SBR/SBS that really aren't, but the ATF seemed to think so upon further reflection, even with ATF letters, etc).
Find out what shotgun that is and let us all know...we could either dispel the myth of an easy conversion, or see if it's the type of thing that's technically possible but is going to land you in a heap of trouble.
Yes, you’re correct. He could get a $250,000 fine and 10 years prison for “manufacturing a post-1986 machinegun”.