I call BS. Civilian AR-15 pattern rifles - aka modern sporting rifles - are significantly different from M-16 in one very important aspect - "select fire" or selective fire capability.
M16s have the capability to shoot semi-automatic, but they also have the ability to fire in burst (3 round) or full-auto mode. Civilian AR-15s are semi-automatic only.
I can hear the libtards out there right now - those with a modicum of firearms knowledge - saying to themselves "Yeah, but in virtually all other respects a civilian AR-15 is identical to a military M16..." Sure, you can play operator wanna-be and deck out your AR-15 to be just like what your favorite military branch/group uses, your favorite TV/movie action star, or the simulated one you have in COD...
But it still differs in that one very important (not indistinguishable) aspect: it is a semi-auto. If rate of fire is not an important discriminator, then why are there "bullet buttons"??? Why are there magazine capacity limits? Seems they have already acknowledged they'd like to limit rate of fire - so it must be an important characteristic of a firearm. That contradicts the claim that a semi-auto is "indistinguishable" from a full-auto or burst-capable firearm. You can't have it both ways Cali.
{Judge} Staton, extensively citing briefs in the case from anti-gun groups such as the Brady Center, Everytown and Giffords...
These rulings are based solely on propaganda from anti-Constitutional groups.
No real firearms experts input is allowed.