I have one made in 1970 that I got off a gun forum for $360 + $30 FFL in 2002.
The firing pin strikes are not reliable with moon clips I have, so I have always used auto rim brass.
The most power I have got out of it is with:
a) 230 gr FMJ Montana Gold 1.4" 24 gr H110
b) 300 gr cast 1.55" 17 gr LIL'GUN, roll crimp
Clark Guns [no relation] has been converting 25-2s to 460 Rowland for 15 years, which is higher pressure than my loads, but I think my loads, with longer OAL, kick just as hard.