That question could be answered from a number of perspectives. PB was a really easy to ignite powder, usually used in 12 gauge target loads, and friends commented to me about how they liked it for use during the winter, because less easily ignited powders sometimes didn't ignite during the winter. My recollection is that it was discontinued by the manufacturer. Its name came from "Porous Base", shortened to "PB". It was a nitrocellulose based powder, with no nitroglycerin, so it bulked up well. The marketing that I still see on seller websites indicates that IMR was trying to sell it to pistol shooters, but that's not something I've heard shooters say. If you look at a burn rate chart, you can see the neighborhood its burn rate is in, but that rate actually varies: Powder Burn Rate Chart NEW | Load Data Article
If you are loading 12 gauge target shotshells, I would look at something like 700X or International Clays. I have burned a lot of 700X over the years in roughly 1 ounce 12 gauge skeet loads, but I've recently got a lot of Hodgdon International Clays cheap and have been using it with 7/8 oz Skeet loads. If you are loading pistol, I would look at VV N320 or 231, but if you want something that bulks up a lot in a pistol case maybe you want to look at Trailboss.