My favourite rifle for practising is my CZ .22 Magnum.

I use it more days than not on my farm, don't really shoot targets at all with it - except when I blame poor shooting on the sight in rather than missed shots.

Just lots of rabbits and the occasional hare and fox. Don't need to reload for it, relative cheap to feed and the CZ has a larger rifle feel to it compared to a normal rimfire so good practice. Nice and accurate too. My only complaint is the mid-priced scope (a Tasco 2 - 7x) which doesn't have good enough resolution in lower light when it is most needed.

With the dog took it for a walk this afternoon and missed one off-hand head shot at a rabbit and one dead on, so good field practice.

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For big game practice I use my old faithful my Parker Hale .30-06.