When I was working on my own loads, I kicked things off with the published max of 8.2 grains and slowly crept up in 0.1-grain increments, keeping a close eye on pressure signs like I was in a high-stakes game. I pushed it to 8.4 grains in a 5" barrel and hit around 1210 fps, but I decided to back off once I noticed some flattening on the primers and a bit of sticky extraction. It wasn’t a full-on disaster, but it was a clear signal that I was dancing on the edge of safety.
One thing that really stood out to me is that HSTs don’t always act like other JHPs when you push them fast. I actually got better terminal performance in the 1150–1180 fps range compared to when I cranked the speed up higher. Once I hit 1200 fps, I saw the petals sometimes peeling back way too far or even fragmenting in a way I wasn’t thrilled about. So, while chasing that velocity is definitely a thrill, I ultimately found my sweet spot with a load around 8.1 grains that gave me a solid 1175 fps and some really consistent groups.
