What US states are commonwealths?
Since you specified "4", I'm guessing you mean the Commonwealths of Massachusetts, Virginia, Pennsylvania and Kentucky.
The term doesn't actually mean anything legally, it's just the official name of the state (instead of the more common "State of...").
The following US States style themselves as commonwealths:
In the United States Massachusetts , Kentucky, Pennsylvania, and Virginia are styled commonwealths, not states, although functionally there is no difference. The United states also has two insular territories that are styled commonwealths. They are the Commonwealth of Puerto Rico and the Commonwealth of the Northern Marianas Islands..
Physiographically, Nevin Fenneman's paper Physiographic Subdivision of the United States, published in 1917, identifies 25 provinces of the contiguous United States. Geologically, there are 10 provinces in the contiguous United States according to the US Geological Survey. Politically, the US is divided into states, territories, and commonwealths, but not provinces.
With regard to the United states, a "commonwealth" is "a self-governing autonomous political unit which has voluntarily associated itself with the United States." One example would be Puerto Rico. True commonwealths have a certain degree of government separate from the United States, and their citizens lack certain rights and responsibilities as compared to the citizens of US states. For example: Puerto Ricans do not pay income tax to the IRS; they have no voting representation…
Virginia, Kentucky, Pennsylvania, and Massachusetts officially call themselves "commonwealths," as in "The Commonwealth of Virginia." However, there is no legal distinction between a state that calls itself a "commonwealth" and a state that does not. All four of those "commonwealths" are states of the United States of America, just the same as the other 46 states.
Why do Americans say the US has 50 states when it really has 46 since 4 of them are Commonwealths. Kentucky Massachusetts Pennsylvania and Virginia.?
A state and a commonwealth are one in the same by definition. The US Government has the idea that all of the states and commonwealths are the same. The difference is how they govern themselves. A lot of times commonwealths consider themselves to have a sense of "sovereignty" within the people themselves. So essentially one could argue that it's just a pride thing.
The term 'commonwealth' really does not differ from state in the US, as it functions the same. Some states have referred to themselves as a commonwealth in their state constitutions because in revolutionary times, commonwealth was a term used to describe a state or nation where the people came together by mutual consent.
Do all states require you to fill out paperwork when you buy a gun so that they know who bought the gun?
There are no states that aren't states, although some are legally called "commonwealths." However the District of Columbia (which is coterminous with the city of Washington, DC) is not a state although it shares several attributes. *That is the likely source of this question, as a miscopied variant of the related question below.