Please take a look at the lower left of this page. If this is your source, you will see that these bullets are in fact
plated as opposed to FMJ.
http://powerbondbullets.com/about.html
If so, I would compare the bullets to lead in reloading them. As a general rule when loading plated bullets, you should use the same loading data as a cast bullet. I believe the load data you shared is for a
jacketed 165g Sierra bullet.
I would consider dropping back on the low charge and start under the 4.8g of 231 noted. How much is the question? That I cant help with.
YMMV