im a huge fan of the .303 but heed my warning, reloading .303 brit casings is a true pain in the arse and there is a serious lack of light weight high ballistic coefficient bullets in .311'' needed for the .303 to perform beyond 300 yards. find good brass, learn how to anneal it (easy enough with a blow torch set in a purpose built fixture) and dont ever use it more then 5 reloadings if you plan to load on the top end load density. the sloping case and semi rounded shoulders of the .303 make it stretch beyond that of other options in its class. the chamber dimentions of the .303 have also changed throughout the years. when i fire a new production hornady bullet out of my 1914 h&h mk.III HT the shoulder gets blow forward about 0.050 but when i shoot the same bullet from my 1943 bsa no.4 the case almost doesnt expand at all.