To answer your original question a bit more gently...
The 303 British, 7.62x54R, and the 7.7 Arisaka (Jap) all use .311" bullets, whereas the 308 Winchester uses .308" bullets and its metric designation is 7.62x51.
Loading .311" bullets in a .308" bore is very dangerous! I
It is quite common to reload for those older .311" military rounds with .308" bullets, because they are readily available. What results is safe, although oftentimes not very accurate.
The most important thing to grasp from your question is to ALWAYS use ammunition that matches your firearm. If you not 100% sure of what you're doing don't take any chances; just look at the headstamp on the brass and make sure it is exactly what is marked on your gun.
Merry Christmas.
The 303 British, 7.62x54R, and the 7.7 Arisaka (Jap) all use .311" bullets, whereas the 308 Winchester uses .308" bullets and its metric designation is 7.62x51.
Loading .311" bullets in a .308" bore is very dangerous! I
It is quite common to reload for those older .311" military rounds with .308" bullets, because they are readily available. What results is safe, although oftentimes not very accurate.
The most important thing to grasp from your question is to ALWAYS use ammunition that matches your firearm. If you not 100% sure of what you're doing don't take any chances; just look at the headstamp on the brass and make sure it is exactly what is marked on your gun.
Merry Christmas.
