loads for h&r buffalo classic

[deadkelly]

iam looking at getting a h&r buffalo classic in 4570,i wish to use this on australia's big game buffalo,scrub bulls,camel,donkey's ect.most loads i find are for 24in barrels,iam sure fine tuneing for the 32in barrel will give better results,any info would be much appreciated,and save me money on powder.hi to all .ps any recommended bullets?thanks deadkelly.