I'd be more than eager to run the 55 TTSX if I were allowed to take the .223 after deer where I live...
There's a handful of bullets that will kill deer reliably.
Over the years we've killed game with 64gr. Power Points, 60gr. Partitions, 53gr./55gr./62gr. TSX, 55gr. TBBC, and even the 45gr. Nosler Solid base in a lowly .22 Hornet.
I've never taken game with them, however, I've heard good reports on the 75gr. A-Max. If your rifle will stabilize the bullet, from all accounts it's an excellent choice.
There's also the 69gr. Scenar to consider.
Personally, if not able to utilize the A-Max bullet, my pick would be the 62gr. T/TSX
