ANYTHING, and I mean absolutely ANYTHING that prohibits ANY citizens from obtaining ANY type of firearm or ammunition for that firearm is considered infringement. So, technically, every single law on the books concerning guns, the very existence of the BATFE, background checks, the NFA, the GCA of '68, the Hughes Amendment, etc... goes against the 2nd Amendment. The 2nd Amendment is NOT a limited right, in its original context.
Granted, Big Brother and pinheads in the judicial system have bastardized it to the point that has now become a limited right, but that does not mean that it was ever meant to be limited in any way, shape, or form. Just read the wording. Also, those that say, "yeah, but it says for a well regulated militia..." The 2nd Amendment is a 2-part sentence. The part that says "A well regulated Militia, being necessary to the security of a free State" is simply making a statement. It is stating that a well-regulated militia is absolutely necessary to ensuring the security of a free state. And being that in those times, because we didn't really have a large official military like we do today, it also counted on any male of fighting age as part of the militia, so that includes ALL of "We the people". The 2nd part is the most important one...Where it says, "The right of the people (all citizens) to keep and bear arms shall NOT BE INFRINGED."