Rumor is that Hell is busily remodeling the Malebolges to create a new level for politicians and physicians who betray their constituents, their oaths of office, and their oaths as healers for power. They foresee a massive influx, I'm told.
"Regulated" in the 18th century was often synonymous with "trained" or "functioning according to its purpose." Like a well-regulated clock. Something that is regular, in the positive sense. Here is a link to Wikipedia which discusses this:
The Second Amendment could be rendered:
"Because of the need to be able to muster an effective, disciplined force of lawful civilians into a defensive force to protect the community in times of civil disorder or external threat, the government shall not unduly restrict the natural right of the citizens to have and use personal weapons suitable for that purpose."
Which is why I believe the Second Amendment probably means the government cannot simply ban semiautomatic rifles, because those are the basic, modern type of personal firearm one would use for defense and order. However, I believe the second amendment allows, and perhaps demands, that someone exercising that right not be someone who would be excluded from being deputized or drafted, whether due to serious felonies or inability due to serious psychological or mental inability. I think the question can be posed, "Do you need a 30 round magazine to use on a regular basis, in order to meaningfully exercise that right?" And I think the answer is probably not, you can probably participate in suppressing a riot five rounds at a time. I think it's reasonable the government insist on some limits on items that are more likely to be used for mass murder than a reasonable, lawful act. So, for instance, high capacity magazines might require a special license. Because your use and training in a semiautomatic rifle could be of use in a "militia," said if you were deputized, or joined a service branch, I think a case could be made for "will-issue" licenses to people without a criminal history. That is, if you pay the license and fulfill the other requirements, the government probably can't restrict you from owning such a weapon and practicing with it on a firing range.
Arguably, your Second Amendment rights could be modeled after European models, where rifles are assigned to people and the keeper practices regularly at a training center. But that does cut against a substantial amount of precedent.
Notably the Second Amendment concerns the natural right of self-defense and community defense, not some abstract need to at a later date possibly dismantle the government itself.