I got a question for you gents...
I've never owned a gun, and no one in my family has either.
However, recent evidence that a massive mountain lion has taken residence on our property has began to worry us as my mother and father are constantly walking through the woods and working outside. So we are considering buying somekind of rifle for a worst case scenario, kitty is outside in the yard and looking hungry possibility.
But knowing jack shit about guns, what kind would be best to get? I mean, we don't want to spend a lot because there is a very real possibility the thing will never be fired, but just in case, what kind of gun would be appropriate?
That's a hell of a situation. Since no one has every touched a firearm in your family, I am going to give a different suggestion.
This situation depends on a few things. Are you intending to hunt this mountain lion down or is it going to be a spontaneous situation that you are anticipating? If its a "Holy crap! There's mountain lion out front!" situation, get a shotgun. A Remingtion 870 is a solid pump action that isn't too expensive. Use a buck shot load or a slug as both will do the job. Shot will allow you more room for error. I suggest a shotgun since you will probably be within close range to see a mountain lion and all you have to do is point a shoot.
If you want to hunt this thing down, get a rifle. Nothing less than a .270. In fact, SWIFT has a rifle for sale. Its a .300 and he's asking a good price. Even comes with a scope. After some good practice, you should be able to put a round downrange 300 yds+ which is completely unnecessary because there's probably not a clear 300yd path through the trees in the woods...LOL.
If you want a pistol, a 9mm will do, a .45 is for sure, and a .44 is too much. I hunted pigs with my 9mm. If I can take down a 200+ lbs pig running at me with a 9mm, then it'll work on a cougar. Plus you can get 15 round mags and since you are a novice, you'll need the extra rounds. Both a .357 or .45 caliber pistol will work, also, but they are harder to handle.
To be honest, the shotgun with a long barrel will be best for you. Regardless of what you get, GO TO THE RANGE. Take whoever might use the gun with you. PRACTICE, PRACTICE, PRACTICE. Owning a firearm is NO joke! In the right hands, you can save your family's life, but in the wrong hands, it can be devastating. Also, if I could make another suggestion, add some motion detector lights to your house. That'll be a really good proactive move.
Take care of this situation as I've heard some bad things about cougars too close to people's homes. Call your local government for advice, also. (ie. park services, animal control, etc) They have been known to catch and relocate animals like this, so you may avoid the situation completely.
Whew...all done. Good luck.