Update on the subject
I have been field testing the Hornady RN (Round Nose) in 270 grains with VV N160 in two loads, one with 75 grains and one with 78 grains. The 75 grains load shoots well together at 50 meters whereas the 78 grain load crosses 7-8 centimeters also at 50 meters. The 78 grains load is not pleasant to shoot and shows an excessive flame.
My concern was that the impact speed was not high enough with the 75 grain load to secure proper expansion in the animal, thus the whish for more speed compromising on keeping the bullets together.
The driven hunts have shown that the 78 grains load with the 270 grain Hornady RN is to powerful and may create a 10 centimeter exit hole when hitting bone on a 40 kilo boar.
On another smaller boar no bones were hit and the exit hole was app 3 cm. doing the meat I noticed that 8 ribs were broken close the spine on the exit hole side. This shows the massive force delivered.
One boar was hit badly, too far back so it was still alive and the dogs were attacking it so I obtained permission during the drive to run to the boar. With one foot and one hand keeping the dogs from the boar I tried to shoot the boar in the neck. The rifle doubled, holding it in only one hand I felt the magnitude of 2 x 78 grains VV N160 and 2x 270 Hornady. The skin on the trigger finger and the next was damaged but that was nothing to the effect on the neck and skull of the boar.
The last driven hunts of the season did not bring any results regarding expansion, but yesterdays walk in the sunny winter forest gave the opportunity to shoot a calf at maybe 175 meters distance. I had left my black Labrador by a tree and closed in on the deer and was ready to shoot only waiting for the proper Hind to show enough body to hit the heart & lungs. Akon, my lab, was not happy with the situation where I am hunting and he is waiting so he started Houling like a wolf. The deer all looked in my direction ready to depart, so I knew that it was now or newer (we have to fill the yearly quota on Hinds before the 15 of January where the season closes) the deer dropped on the spot, shot in the front, quartering out just above the heart. Normally I would not have taken this kind of shoot, but the season is closing and the quota has to be filled. The exit hole is 2 cm and I am looking forward to see what damages it caused inside. The lungs were more or less intact.
The deer where enjoying the warm rays of the sun after a very cold night with wind and low temperature. I know that because I was walking most of the night looking for boars and slept only a few hours in the car before looking for deer in the morning.