From a puny 338-06 with 210 ttsx, at about 125 yards, mine broke a 50 inch bulls neck, through the opposite shoulder on the way out, and caught by the skin.
Not bad penetration on something over 1000 pounds and from that small of a round.
TTSX do fine for us and I've actually yet to have an issue with an Barnes bullet.
I can't say the same for the others. All of the others. I'm sure the Barnes day will come though sooner or later.
I'll take a barnes over a partition any day if I have the choice.
RE 165 non mono for a 300 mag... thats just a bad choice really. Even a 180 partition would not hold togetehr like a ligher barnes.