No idea Mike but I can make a comment on the 140 gr. BT. It was one of the early ones that cost me a deer and my right knee. I suppose the knee was my fault as I tried hurrying up the ridge to look down into the gully the deer ran into. The hit was well placed but the bullet blew up on a rib making an ugly and most likely shallow wound. Velocity was a chronographed 2800 FPS.
I believe that the early 140 gr. BT that come in 100 bullet boxes had the stiffer jackets when Nosler changed to 50 bullet boxes for the BTs. I have yet to try the newer version of the 140 BT in my 7x57.
Right now, I'm trying to get the 150 gr. 7MM ABLR to shoot in one of my 7x57s and in a .280 Rem. but so far no cooperation. Also have a series loaded up to try the 160 gr. Gram Slams once the weather cooperates. It's our rainy (monsoon) season and the range is a boggy mud hole.
Paul B.

Our forefathers did not politely protest the British.They did not vote them out of office, nor did they impeach the king,march on the capitol or ask permission for their rights. ----------------They just shot them.
MOLON LABE