after speaking with the ballisticians of two powder companies
one of which is intimately familar with the Blackhorn 209 product,
I understand now that the MuzzleLoader companies have to
regard most muzzle loader shooters as idiots because of
the age old practice of loading by volume. With the much
more powerful nitro based smokeless powders and even the
Blackhorn 209 they cannot risk an old timer loading up his
scoop with a modern nitro based smokeless powder and
blowing himself up. They flatly say they dont think they
can trust muzzleloaders to weigh their charge loads.
( the gun makers... the powder makers say they would
be happy if the gun makers would recommend smokeless
powders )
Otherwise almost all the muzzle loader companies could
publish smokeless powder loads that do not exceed the
pressure capabilities of their guns.
Two examples that were given to me because they are
published are the 50 cal examples of compressed 50-70
and 50-90 metallic cartridge loads using Blackhorn209.
It was pointed out that these pressures would be the
same in a muzzle loader with same charge and bullets used.
The 50-70 cartridge with 475 gr cast bullet and 37 gr of
Blackhorn209 has a max barrel pressure of 19.360psi
The 50-90 cartridge with 475 gr cast bullet and 71 gr of
Blackhorn209 has a max barrel pressure of 27.610psi
This info can provide a glimpse into what is going on inside
your muzzleloader. An example given of a modern cartridge
loaded with smokeless powders and conforming to muzzle
loader pressures was the Springfield TrapDoor 45-70.
These loads have an approx 18,000 psi pressure max.