Here's some evidence to take into consideration:
At the time of the founding, as now, to “bear” meant to “carry.” See Johnson 161; Webster; T. Sheridan, A Complete Dictionary of the English Language (1796); 2 Oxford English Dictionary 20 (2d ed. 1989) (hereinafter Oxford).When used with “arms,” however, the term has a meaning that refers to carrying for a particular purpose—confrontation. In Muscarello v. United States, 524 U. S. 125 (1998), in the course of analyzing the meaning of “carries a firearm” in a federal criminal statute, JUSTICE GINSBURG wrote that “{s}urely a most familiar meaning is, as the Constitution’s Second Amendment . . . indicate{s}: ‘wear, bear, or carry . . . upon the person or in the clothing or in a pocket, for the purpose . . . of being armed and ready for offensive or defensive action in a case of conflict with another person.’” Id., at 143 (dissenting opinion) (quoting Black’s Law Dictionary 214 (6th ed. 1998)). We think that JUSTICE GINSBURG accurately captured the natural meaning of “bear arms.” Although the phrase implies that the carrying of the weapon is for the purpose of “offensive or defensive action,” it in no way connotes participation in a structured military organization.
From our review of founding-era sources, we conclude that this natural meaning was also the meaning that “bear arms” had in the 18th century. In numerous instances, “bear arms” was unambiguously used to refer to the carrying of weapons outside of an organized militia.
The most prominent examples are those most relevant to the Second Amendment: Nine state constitutional provisions written in the 18th century or the first two decades of the 19th, which enshrined a right of citizens to “bear arms in defense of themselves and the state” or “bear arms in defense of himself and the state.” It is clear from those formulations that “bear arms” did not refer
only to carrying a weapon in an organized military unit. Justice James Wilson interpreted the Pennsylvania Constitution’s arms-bearing right, for example, as a recognition of the natural right of defense “of one’s person or house”—what he called the law of “self preservation.” 2 Collected Works of James Wilson 1142, and n. x (K. Hall & M. Hall eds. 2007) (citing Pa. Const., Art. IX, §21 (1790)); see also T. Walker, Introduction to American Law 198 (1837) (“Thus the right of self-defence
guaranteed by the constitution”);see also id., at 157 (equating Second Amendment with that provision of the Ohio Constitution). That was also the interpretation of those state constitutional provisions adopted by pre-Civil War state courts.9 These provisions demonstrate—again, in the most analogous linguistic context—that “bear arms” was not limited to the carrying of arms in a militia.
The phrase “bear Arms” also had at the time of the founding an idiomatic meaning that was significantly different from its natural meaning: “to serve as a soldier, do military service, fight” or “to wage war.” See Linguists’Brief 18; post, at 11 (STEVENS, J., dissenting). But it unequivocally bore that idiomatic meaning only when followed by the preposition “against,” which was in turn followed by the target of the hostilities. See 2 Oxford 21. (That is how, for example, our Declaration of Independence ¶28, used the phrase: “He has constrained our fellow Citizens taken Captive on the high Seas to bear Arms against their Country . . . .”) Every example given by petitioners’ amici for the idiomatic meaning of “bear arms” from the founding period either includes the preposition “against” or is not clearly idiomatic. See Linguists’ Brief 18–23. Without the preposition, “bear arms” normally meant (as it continues to mean today) what JUSTICE GINSBURG’s opinion in Muscarello said.
Source: http://www.supremecourtus.gov/opinions/07pdf/07-290.pdfAs the Supreme Court notes, state constitutions spoke of bearing arms personally, not as part of any organization. This is the most relevant and analogous type of original historical source--contemporary legal documents, constitutions even.
The first time the Supreme Court addressed the Second Amendment, it called it a "right of person." It spoke of citizens being able to keep and "carry" arms wherever they went--carry was obviously a synonym for "bear" as far as they were concerned. And there's more where that came from. If you read original sources directly on point--old Supreme Court decisions speaking to the Second Amendment, old state constitutions, etc.--you may form a different opinion.
Take your time.