I'm sorry to hear that you lack the imagination or empathy to make the connection at various levels.

The first is that the topics are quite heavily associated with the traditional political spectrum. In my observations, left-leaning politicians and parties are in favour of reproductive rights and health funding, while also more strictly regulating firearms; conversely conservative parties are not fans of unrestricted abortions, yet want less restrictions on firearms. This applies outside of the United States, as well.

Connected to this is the legislative aspect of both subjects. Both are at the centre of various controversial pieces of legislation, and judicial interpretation. The limits of what is permissible; the level at which the state can interfere in the application of the right; where one's rights can impede on the rights of others; and so on. Backbenchers of any party like to bring up these topics when party leadership is too timid to, or when there is insufficient political capital (or desire) to encroach on something that is so polarizing and only affects a (admittedly sizable, but ultimately) minority of the electorate.

With legislation comes enforcement and with enforcement of laws restricting anything with sufficient demand, the black market fills the role. 'Vice' prohibition is a unanimous failure as a concept; it merely brings the trade to the underground. As we have learned time and time again, the black market brings with it violence and various other associated crimes and monumentally increases the risk for those who do seek it. Guns smuggled or backalley abortions are undeniable. The act of legislating against something does not make it disappear, and has with it a plethora of (mostly undesirable) circumstances and fallout.

Finally I see the moral philosophical side, where the underlying questions such as "what is autonomy?" and "to what degree am I free to act in my own interest?" show the level by which these commonly black-white conclusions are undoubtedly complex greys. And it is often political necessity by which compromises (or status quos) are compromised. I have certain views on abortion, as well as on private ownership of firearms, which you may be able to deduce and you are free to think of what you will. With that being said, I hold the positions that I do, as well as the political positions I hold on theses topics (which are not necessarily the same) following a best effort to understand and appreciate the complexities of how those around me perceive the world which we share. How they view their own autonomy and morality. And how we as the individual interacts with the society around us and ultimately beyond us.

tl;dr I disagree and you're simplifying it.