Riverbrand 303 Sporter box - what caliber?

Hi All
I have this box from Riverbrand. It is marked as 303 Sporter with a 140 gr projectile.
What actual caliber was it? 7.7 x 54 or 303-25 or 303-something else?
Thanks!

It is the standard 303 British loaded as a “sporting” load.

Thanks but what does that actually mean?

Says it on the packet…jacked soft nose…ie gilding metal jacket with exposed leadcore nose.
So that it expands when striking target ( whether animal or range target ( steel or wood).)
Doc AV

Maybe I wasn’t clear. My question is about what the caliber is, not what type of projectile it had.

To repeat: Does 303 Sporter mean 303-25 or other wildcat or does it mean 7.7 x 54?

Thanks

No, it means .303, period.
If it was .303/25, or 7.7x54R ( the
NSW legal cartridge) or any other variant, the packet would have said so!
Sporter differentiates it from military Full Metal Jacket, which was Not loaded by Riverbrand at all, being available to NRAA club shooters direct from Defence Department.
Riverbrand and Super Cartridge both reloaded once-fired Military .303 cases, both as .303 Sporter, and also other calibres based on .303 cases.
These were Berdan Primed cases
Using RWS #1705 or later #6000 noncorrosive .250" primers.
This reloading gradually gave way to New Boxer primed cases, and the supply of .303 military brass
Decreased after the adoption of 7.62 Nato in 1958-59…although both makers kept reloading 7.62 cases ( also Berdan) until both closed by the late 1970s.

Doc AV

7.7x56mm = .303 British

.303 Sporter = 7.7x56mm = .303 British

7.7x54mm = a shortened .303 British cartridge case to meet legal requirements in some European countries.

Brian

OK, thanks everyone. Learned something new.