I know a little about the 130 gn projectile and the 270 calibre..
There had to be a cut off point somewhere and that happened to be it.
I know a couple of the people concerned with the minimum cal for sambar ,let me assure you the are or were experienced hunters..
Nick Harvey and I discussed this very subject whilst I lived in Ballandean QLD.
Nick was hunting fallow on Warwick Freemans place at the time.
I was using a mod 96 in 6.5 x55 and my mate was using a 270 ruger he bought of Peter Luhrs.
Nick said in his opinion the 6.5 using 140 gn bullets was a better deer rifle than the 270,however on sambar the cut off was 270 and 130 gn projectiles.End of story.

Quote from DCNR brochure.
Centre fire min.legal cal 6.85(270)
Legal case length 51mm (2")
Legal projectile weight 14.91g (130gns)

Black Powder muzzle loader.min cal .45, projectile must be a minie weighing no less than230 gns.
Hope the above has helped.
Al