Trailer the fact the entrance was small we can assume it behaved as it should and never came apart, which is good. I assume the bullet stopped somewhere on the inside if you never found an exit(just came out in the field dressing I guess) and the lack of wound channel would have resulted in the minimal blood trail you encountered. I had the very same thing happen last fall on 2 does with the 140gr TSX, zipped in and out that only specs of blood could be found, like you I watched where the deer went and made the need to track a non-issue(no snow either). I wasn't overwhelmed by the performance on either of these harvests and have since switched back to my NBT load for deer hunting. It comes down to what we expect from a bullet on game, I personally have never been upset to see a large blow out the exit side from the NBT it usually means the deer is down within a hurry and if they do muster a little run the blood trail is blind man worthy.
Good Luck and hope the next time proves to be a better result..though the search for the best bullet will always continue for the handloader

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BTW one of the guys I hunt with is using the Hornady IB this year in his 280 rem, it has performed very nicely in 154gr version. Shot a large body bucklast weekin the forest through both shoulders and it punched a nice hole straight on through and dropped him where he stood (his lungs were litterly jello). He and his boy have taken 4 deer so far with it. I have a box sitting on myshelf that I may try to get shooting for next fall deer season asI'm impressed. Of course can I get them to rival the others on paper is the question that needs to be answered.