Hi Ron, I have a lot of AP100 gunpowder. Just wondering if I could use say, 8gns of AP100 in a 44/40 Winchester Rifle 92 or 94 model instead of the 7.9gns of AP70 which I don’t have any of. AP100 is a slower burning powder. What do you reckon? Regards,

http://www.adi-limited.com/handloaders-guide/

Dear L
If you go to the link above and read the data for 44-40 it does not list AP 100.
We can only conclude that they do not list it for a good reason as if they could, they would as it would assist with their sales . They are well aware that shooters like to use the same powder for as many of there firearms as they can. a flexible powder is a good selling powder. You will also note the huge variation between the quantity quoted between AP 70 and Ar2205 . If they could have fitted it between I believe that there computer program would have computed if it was within there limits. Also they make fair comment about the variations in bore size in 44-40s barrels and suggest that everyone slugs there bore and mic s the result. As a great piece of history could be destroyed. If an adventurous sole did want to work up a load with AP100 after checking bullet size required, start below AP 70 recommendations and in batches of 5 increase each batch by two tenths of a grain and testing with a Chronograph. The desired velocity that you expected from the AP70 might not be attained before signs of increase pressure show occur.
All the best
Ron