303 British or 303 Enfield Whats the difference?

Unless there's an obscure cartridge that I can't remember right now, I think you're referencing the same thing. A No 4 Mk1 is chambered in 303 British. There may be some headstamped Enfield though I've not seen any. What I've got here is just 303 and then date stamped. It was used in the Enfield series of rifles and I think in one of the belted machine guns --- again, poor memory.
I had a No 5 for several years and always bought 303 British ammo for it. Never a problem.
Hopefully, someone else will jump in here and either confirm or say "no, dummy....." with the right info.

303 is the round used by the Brits.

"303 British" is the same round used by the Americans and called the "303British" or ".303 Brit"to help Americans identify it.

Make sense ? The old military surplus stuff just had .303 stamped on it. The American stuff is the one with .303 Brit stamped on it.

Its the same round and its a good round.

AFAIK there is only ever one .303 round, regardless of headstamp markings.

Bullet dia IIRC is .314 and the old milsurp is loaded with cordite sticks - primers chlorate type, corrosive.

More modern loadings like factory Winchester 180 grain SP are good hunting rounds shot thru a nice MkIV. I still get great pleasure eating some milsurp thru my MkV Jungle Carbine :smilez:

303 Enfield first refered to the converted Martini's and then to the very first Enfield Bolt guns, as they where made at the Enfield armory,, then during WW-1 with the advent of the 1917 Enfield it confused the issue a little ,, as the Americans used it in 30-06 and the Britt's in 303 British,, so most Americans just short'en it to 303 Britt, and most ammo compianes in later years followed

Thanks to all who answered, Im always amazed at the Knowledge
level here. It's nice to learn here, and pass it on.