FWIW, I did a comparison on the hanging steel plate at my 500-yard range.
The Sierra 150 SPBT made a very slight dimple. The 165 HPBT made a slightly deeper dimple; maybe 1/16". The 180 SPBT was noticeably deeper at 1/8" or a skoshi bit more, with a bit of splashback of the steel.
You're from BATFE? Come right in! I use all your fine products!