Quite alarmed at some of the advice given in this thread!
Firstly get yourself trained.
Secondly the rifle and calibre you choose will depend on the kind of shooting you do. Germans do a lot of high seat stalking for deer. They also enjoy driven Boar and the optics used for both disciplines are fundamentally different. A gun you will shoot freehand at running targets is different to a rifle shot supported on a stalk.
Don't pick a gun from an internet search. Go and handle a lot of rifles and find what fits you and feels comfortable. A cheap gun will not have good resale value. It's likely that you will end up trading that first gun for a better one so consider its disposal.
Calibre choice is an age old question and is likely to be the reason you trade rifles.
A .308 is a reasonable calibre for most deer species though it might be considered a bit overkill for Roe. However dead is dead. Supplies are plentiful and there is a variety of loading available off the shelf.
It's unlikely you will start hunting and loading your own ammunition so downloading your calibre is not an option day one. As a hunter in Germany I'm doubting your ammunition volumes will merit a reloading set up unless you have deep pockets.
If you are looking at Boar then you start at about 180gr bullets and work upwards. The .308 will do this job but 300 Win Mag is my personal choice for this but it's a beast to shoot with a lighter gun so you should try this before you commit. It's a lot more expensive. Quite a lot of new shooters shy from .308 too. Technique is everything in shooting and experience worth its weight in gold. Take your time.
A stainless synthetic rifle is a great option as it can take a lot of abuse but again it's more expensive. Bringing a rifle in from -13c is going to cause a lot of condensation. Leaving it outside is possibly not an option if you must have the gun under your control
Do the course, handle as many guns as you can and shoot them if possible.
Have fun. What an exciting time for you.
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