Have shot more Nigam or blue bull than most. Well over . . . . Which amounts to 35 years of weekly hunting for the pot.
Not one have I shot in Texas ! Our blue bulls are much larger and the largest I have weighed has been a little over 1000 lbs with horns over 11 inches ; almost or perhaps a record.
The problem with Nilgai is that they are tough and can run nearly 100 yards with a smashed heart. Hit the shoulder aorta and spine and they fall instantly all be it not quite dead. I the real world animals move and bullet placement may go awry. The best rifle is one which is forgiving, has excellent penetration, deviates minimally in thick brush and packs a punch.
I have taken Bos elaphus tragocamelus with 22lr on several occasions but this does not mean that it is suitable for nilgai. The 275 rigby is as good as the 30-06, the 7mm rem mag and 300win mag are good, yet not good enough. The 338 win is I am sorry to say a useless cartridge which exists because the extremely efficient 350 Rigby remained a propriety and thus expensive round. Indeed the 350 rigby would have been the ideal cartridge for Nilgai.
The 9.3x64 Brenneke is a typical theoretical German cartridge. It offers similar ballistics as the 375h&h but is extremely uncomfortable to use, indeed more so than the 458 win mag , 416 rigby, 425 westley Richards 465 India h&h etc. The 9.3x62 lacks penetration and should not be used on nil gain or on dangerous game. I am aware of its reputation in South Africa where it was popular because it was cheap.
I have removed 30-06 bullets from nil gain shot from the rear, which have penetrated upto the kidney region; the wound had healed completely and the animal was in good health !
The 8x68 is again a theoretical invention with little practical use.
Apart from the 350 Rigby the only really practical round is its nemesis, the 375h&h mag. There is no angle from which the 375 holland will not completely penetrate and devastate nilgai. A liver shot with a 30-06 will hardly stop this animal whereas the same shot with a 375 will stop him within 50 yards , if not 20 yards. If you must use a 300 win mag , avoid shooting at running nilgai, for if you should hit him a hands' breadth behind he will take you for a long search.
Rifles heavier than the 375 h&h lack accuracy at longer ranges and hence sere no useful purpose on nilgai. I have taken blues from 3 yards up to 400 yards with express sights. The cheapest federal bullets will do the job although the RWS ammunition is better.
Any medium rifle will do the job but here the h&h does it better and with little fuss. Forget your American calibres, blue Bulls were vermin big game of the British empire and the empire knew how to deal with them.
I apologize for the long reply, I could go on for an eternity on shooting blues for the pot. As you perhaps know , nilgai were not fair game where pig sticking was concerned unlike axis porcinus and leopards.
