All those loads were on the mild side. The case holds 73gr of H2O. With some of the bullets loaded out to 2.9" OAL the remaining case volume is the same or more than the remaining case volume of the .405 Winchester with those bullets. With the short Hornady 300gr SP, for example, the .405 Winchester has a good bit more usable case volume than the .405 Grenadier. But the Barnes TSX loaded to 2.9" in the Grenadier leaves 2 grains of H2O more usable case volume than the same bullet loaded to 3.1" OAL in the .405 Winchester.

I will be playing with more loads. The base cartridge is a 57,000 psi piezo CIP cartridge, same as the 9.3x62 and 8x57JS. The rifle was made for that as well. I prefer to stay well within the pressure limits of the case and rifle. I have no desire to shoot max loads. Still, I think 3500-3600 ft lbs is a reasonable expectation. We will see.