Interesting caliber, at present buying loaded ammo for the 303 Savage is near impossible.
About 4 years ago, I had one in a Savage 99 refurbished for a family friend. He was an older gentleman that was given the rifle as hand-me-down when he was a boy. He hunted with it for most his life and it looked a bit rough. Stock was in dire need of replacement and 95% of the blueing was non-existent. I personally had never had a desire to own one, but after a trip to my local gunsmith, a good tear down, cleaning, re blue, and a new fitted walnut replacement stock... WOW... How cool. Beautiful lines, interesting rotery action design, even a unique brass round counter built into the side of the receiver. Hard to imagine why they ever quit making the model.
I did a little homework after the fact. The round was originally designed in the late 1800's to compete with the 30-30 Win. The caliber was originally designed around the slightly larger 303 bullet (.311), but in the end was mass produced barrelled to shoot standard 30 caliber .308 diameter bullets. Yet, Savage stuck with the 303 name. The original factory loads were centered around a heavier 190gr bullet. Having a but less case capacity, combined with the heavier bullet, factory ammo is a few hundred fps slower the the 170gr 30-30 Win rounds. The older family friend still had a box of original 190gr factory ammo from the 50's. Very cool looking. The tip of the 190gr seated bullets seem to extend out quite a ways from the end of the case neck. Almost reminded me of the way the older military 6.5x55 Swedish ammo looked. I have to imagine that would have given the 303 Savage round great stability in flight. Even with the 303 Savage round being 300fps slower then the heaviest 30-30 Win rounds, the heavier 303 bullets had to produce good knock down energy. Everything about the rifle and cartridge was fascinating to me.
In regards to finding loaded 303 Savage ammo... Before the Obama scare induced ammo crisis, a little over 3 years ago Hornady made a limited run of the obsolete 303 Savage ammo. It was only offered in 170gr loads, yet I picked the old boy up a few boxes of the ammo anyways. The newly ran 303 Savage head stamped brass was worth the cost of the loaded ammo alone. Out of curiosity, the only ammo I have recently seen available for the 303 Savage is custom made utilizing 30-40 Kregg brass.