Pistol to rifle conversion kits -- avoiding NFA.

Got an interesting question about pistol to rifle conversion kits, and whether they were NFA.  Although somewhat complicated, the entire matter is determined per ATF Ruling 2011-4, which can be found on the ATF website.  In essence, where a rifle is made from a pistol, or from a parts kit where a conversion for both pistol and rifle are intended -- as long as the rifle meets all non-NFA specs -- it is legal, and the conversion can go back and forth so long as the pistol conversion and rifle conversions are non-NFA.  On the other hand,  a pistol cannot be made from a firearm originally designed solely as a rifle.  That is NFA, and illegal no matter what!  Of course, we are talking about only rifled barrel weapons here.  Smooth bore is an entirely different explanation, as I'm sure you understand.  Hope that explains it.   Of course -- non-NFA means the firearm meets all length and other requirements so it is not a short barrel rifle, or pistol with a shoulder stock or foregrip.  You can find that info in the new 8th edition in Chapter Seven.