2.4 grains gives you over 1000 fps?
You are insufferable.
Looking at my notes, the gas seal style brass typically achieves 890 fps with 2.4 grains of Titegroup and a 90 grain projectile as confirmed by chronograph. If you add more powder, the projectiles typically go faster, but the object of the exercise was to come as close to original specs as possible with the exception of using modern available powders. The commercially available cartridges for this gun produce I also put together non-gas seal style cartridges that I make out of brass originally intended for 32-20 cartridges.
I will repeat for the third time, the point of my original post was not to get into extreme minutia about specific numbers, but only that tiny amounts of propellant contain a surprising and dangerous amount of power. 2 grains or 5 grains or even 30 or more grains as used in full size rifle and shotgun cartridges are all still just fractions of an ounce. 1 ounce equals 437.5 grains. Your mocking and nitpicking of this point is puzzling.