So I have two: The one that evokes the most memories and the one I consider my favorite, go to rifle.
The first is a Ruger No. 1 in .270. I purchased it in 1975 at the Rod & Gun Club in Wertheim Germany - a now long abandoned US Army Kaserne in Germany. Over the next 4 1/2 years, I took 5 red stag, numerous wild boar, and dozens of roe deer. While there, a gunsmith friend sent it to Ferlach Austria where the receiver was engraved with a stag on one side and a buck roe deer on the other. Subsequently, it has taken a dozen or more whitetail. It still shoots 130 -150 gr almost anything MOA or better.
However, my favorite hunting rifle is without question is my Blaser R8. With .375 or .300 Win Mag barrels in place, there is simply nothing like it in my experience. It is supremely accurate, blazingly fast, and has the finest ergonomics of any production rifle that I have ever held. It also packs into a very small package for international travel. Simply the best.
With both these rifles I have had some amazing experiences, and we often sit down together late in the evening with an oily rag and a single malt to relive those adventures.