It's not that important for her to like guns and shooting, but it's important that she not hate them. Most of all, it's tremendously important that you get things out in the open quickly rather than having them crop up later when it's harder to work things out.
A coworker of mine married a woman who wasn't into guns. But she didn't have any problem with him having guns and shooting them. At least not until she got pregnant. At that point she laid down an ultimatum and he was forced to get rid of all his guns. That was years ago, and as far as I know, he still doesn't have any firearms in the house.
I'm not saying that you should bring up the topic of children and guns on the first date, but I'd certainly want to have talked about it a couple of times before things got really serious.
A lot of people think that the opposite situation (a mate who loves guns & shooting) must be ideal, and while it's tremendously better than marrying someone who hates guns, it has some minor disadvantages too. My wife likes shooting, and as a result, we do most of our shooting together.
This shouldn't be seen as complaining, but in the interest of total honesty, I have to point out that because we do most of our shooting together, everything costs more. I pay an extra range fee, an extra match entry fee, an extra ticket into the gun show, more for ammo and targets, more for cleaning supplies, and yes, more for guns. On the other hand, it's very simple for me to justify a large ammo buy, a new gun, more magazines, etc. because she understands and is often getting the benefit of those things too. And I don't have to trade a load of husband points to go to a gunshow because she understands the attraction and usually wants to go with me. Of course, there can be a bit of a downside to that as well, because although she wants to go, she usually doesn't want to spend nearly as much time there as I would. A similar situation can crop up with a range trip when we both go--it's not uncommon for me to be not quite ready to go when she's had enough.
So there are benefits AND disadvantages to having a mate who shares your hobby.
I would guess that the absolutely ideal situation would be someone who enjoys guns and likes shooting them but maybe isn't into them as much as a dedicated hobbyist would be. Maybe even someone who sees their value as self-defense tools but doesn't care much about the recreational aspects of firearms. Someone who will go to the range with you once in awhile when you ask and who will genuinely have fun on those occasions. But someone who doesn't necessarily want to go every single time you go and who doesn't feel left out if you want to run to the range or the gunshow by yourself on occasion or even most of the time. Someone who doesn't have a problem with guns in the house and maybe even has one or two of her own but someone who doesn't get a yen for a new firearm too often.
One of my coworkers has a wife who fits that description and he's pretty happy with his situation. Although, come to think of it, I believe he thinks he'd be better off if she were more into guns. Could be a grass is greener thing...
Change steer to horses and you have my wife. 