I use the FLS Lee on my 303's because I am running 2 No.4's 2 x MkIII's so to save having to sort brass I just FLS and they fit all 4 just recently I won the state titles in the "As issued" invitational shoot with my No.2 - No.4 shot over 3 ranges multi positions so the Lee's work.
Jim mentions the brass shortage we have that here as well for some reason we have not been able to buy Remington 303 brass for the last nearly 2 years in Western Australiaicon