I use HP-38 too. Well I used to. I use Titegroup now. I use it for all my handgun loads except really heavy 44 mag stuff. Titegroup works better in low volume loads in large cases. It is king for 45 Colt. The nice thing about Titegroup is it is not position sensitive. Meaning it does not matter whether is is next to the primer or the bullet. You will see cowboy action shooters point their gun up in the air before they shoot to get the powder againt the primer. That doesnt matter with Titegroup. HP-38 is position sensitive. With HP-38 if you point the gun at the ground before one shot, then toward the sky before the next shot, there will be a noticable difference in velocity.
Not so with Titegroup.