Thread: Front on shots at Deer.

I was looking through the ".223 on deer thread" recently and saw a couple of posts about deer being shot front on and escaping.
I personally know of 3 instances of this happening so though I would relay them and see what theories people come up with. I am obviously not the only one to have come across this before.
The first was a friend Sika hunting during the roar. He roared up a stag and shot it front on at (according to him) about 30m. It turned and ran off and was not found after an extensive search. He did not find any blood. Did he miss altogether? Maybe, but knowing him I would be surprised if it had been a complete miss at that distance. He was shooting 130gn SSTs from his Winchester .270win.
The second occasion was another friend (very experienced and competent hunter) who was out with his son in Sika country. An average Sika stag came over a small brow and my mate shot it front on and according to him "bowled it flat on it's back". Once again the range was short (<50m) and the hit was definite. They walked over to the animal, put their rifles down and prepared to start butchering it. My mate, with knife in hand, said he couldn't believe it when the stag jumped up and ran off down into a creek and up the other side out of sight! They tracked it for a while with very little blood to follow, and after 2 hours gave up the search. He was shooting 130gn Hornadys from his Sako 85 .270win.
Finally it was my turn. Again a Sika stag, average size body 6 pointer. I had roared him in and he was sideling around the head of a gully on a game trail at my level. I was tucked behind a Punga trunk and knew that if he kept to the trail he would appear front on to me at less than 5m away. As he briefly went out of sight I knelt down and put the rifle to my shoulder. He appeared and stopped at 6 paces. I fired into the center of his chest and he spun around and ran back the way he had come. I listened to him crash off and thought I would wait for 5 minutes before going to retrieve him. Long story short, I spent over an hour looking for him that day and an hour the following day. The bush was relatively open and I combed a huge area in my search. Again there was very little blood and being red/green colour blind I find it difficult to see it anyway. I was very confident I had made a good shot and at 5m why shouldn't I have been. I was shooting 140gn Accubonds @3000fps from my Ruger .270win.
Now some of you will have noticed a couple of common traits to these 3 stories. Firstly they were all Sika stags but I consider this a coincidence. Secondly, we were all using .270 Winchesters so the .270 haters can be first to reply to this. Could we all have just plain missed? (In the second scenario obviously not) or is it something else. I have my own thoughts on what has happened in these situations but would be interested in what others think.