Well ok lets say u can load ur 38 brass to the same pressure.
Do you have a way to measure that ? 38 cases are smaller. All published data for 38 will be to the lower pressure.
So what is ur plan ? Load it till it blows up then back off a bit in the next gun ?
You have NO WAY of loading 35k psi loads in a 38 case unless u have a pressure test barrel, strain gauge or something else I dont know about.