They appear to be, the 120 gr. wider than the 140. But, when I measure them they come out the same width. The Jacket on the 120 is thicker and the lighting of the shot all tend to make them appear so. At any rate, the jacket on the 120 gr. bullet is much thicker all the way through. That would make a significant difference in there terminal performance assuming the same jacket material.
I talked to my buddy last night. He's fascinated as well.
He tells me Hornady did the same thing with their 139 gr. BT. The jacket on it is much heavier than the jacket on their 139 gr. flat base. The iron ram shooters requested it.
I understand the well thought of Nosler Solid Base bullets are back. I saw a post over at Accuratereloading.com on their Reloading Forum about them. The 150 gr. .284 and the 130 gr. .270. I dunno about any others. My buddy says they work much better than the BT's on all sorts of game. E