Before my last purchase from Bob (the last name is Cauterucio), he confirmed that he is no longer making any 7mm 176s, only the 189 grain 7mm bullets. He also confirmed that the 189 grain pill is identical to the 176, only heavier as he now completely fills the jacket with amalgum.
I've been warned by two different smiths that the 189s may need an 8.5 or potentailly 8.0 twist to stabalize, and that the 9 twist in my 7WSM may not get the job done (I assume that faster is better, but my stabaization formula is also showing that a 9.0 may not stabalize teh bullet at 2,940 fps.) I have not yet tested them so I can't answer teh question for oyu, only bring it up so that you are aware of the issue.
Look at this page about 1/3 the way down and you'll see a picture that I took of the length differences between the 7mm Berger 180, Cauterucio 189, JLK 180 and Sierra 175.
7mm Cartridge Guide