Keep in mind that when the 2nd amendment was written and ratified, the fledgling USA had no standing army. An armed populace was its only defense against other nations.

Times have changed. No one needs a Bushmaster, AR-15, AK-47 with massive clips for self defense. If you want one, it should be extremely difficult to obtain one and equally difficult to retain one. And, you cannot sell one without a whole lot of scrutiny and regulation. Close the gun show loop hole(s). Extensive background checks should be required for all firearm transactions, period. None of that infringes on your rights of ownership.