Won't argue with what you want it to do, but some of issues aren't well considered.
1) Shortness is overrated. Storing a rifle will involve taking up more space than a pistol. The difference is you can access a pistol and use it from a weak side upper body holster, but no rifle will allow it. They are just too bulky and long in the one area that makes them a rifle - the barrel.
Another problem is the folding stock. If you really need the rifle and have finally fought your way to where it's stored, you will need it. Unfolding the stock to get the required accuracy to shoot 200m means more delay, or accepting that the limited supply of ammo can be wasted on 10MOA shots. Using the rifle also means you won't be in the vehicle, you weren't in full battle rattle, and the storage location would be secure and very likely concealed or hidden. Exposed guns left in eyesight get stolen. This rifle will be in a rack behind a pickup seat, in a seat cover pocket under it, or back in the rear of a bucket seat model SUV. The few inches more in length won't be a sufficient deterrent in storage, but might be a disadvantage in use if the stock is folded. Exactly why folding stocks aren't the #1 choice in armored vehicle carry by soldiers - they get out to shoot them. Otherwise, they use the organic ones mounted on it.
2) Long term storage of a carbon steel based weapon inside a vehicle is a horrible thing to do. Cars and trucks retain a lot of humidity, and guns rust. Changes in temperature create so much condensation that a stored gun in a case will actually swim in water over a few short weeks in spring. What gun you pick should be made of noncorrosive materials that put up with that - stainless marine models, or forged aluminum. At a minimum, parkerizing, nitriding/ion treating, and a serious attempt to keep it well lubed is necessary.
Having seen the finish destroyed on blued steel guns by storing them in a van for two years, the equally resulting rust and corrosion in the interior and barrel of the gun mean that milspec combat grade is a minimum. That also goes to the ammo - a brass case left in a chamber stored in a humid environment collecting condensation? Aside from any powder residue, do visions of bare chambers and jungle use come to mind? Whatever gun is chosen, it better have a ion/nitrided barrel, and the ammo needs nickel plating, too. Precisely why police issue it, for long term carry in the day. It didn't add to the corrosion problem.
I'm emphasizing environmental concerns because that will be the problem the weapon must endure every day - and if it's out of action pulling it from a sweated, wet carrying location, dripping with rust, what good is it? And not putting it in a case means it will collect dust, airborne grit, and whatever else floats around in the vehicle. Nobody needs to see a french fry stuck in the muzzle from a young passenger.
Frankly, any long gun will do when or if a 200m shot needs be taken, but how well that gun tolerates storage is far more important and needs a lot more consideration. Having used combat grade weapons in horrible weather, and owning someone else's poorly maintained civilian truck guns, it becomes obvious to me where the money needs to go.
