In Handloader #260, Brian Pearce mentions a load using AA#9 and a 255gr Lyman 429244 for just a little over 1200fps and just under a 1" group. Max charge was 16.5gr.

This was in one of the new mid-frame sized Ruger Blackhawks chambered in 44SP and was rated at 25Kpsi. I really like my pair of those 44SP Blackhawks!

A slightly lesser charge was discussed in Handloader #236 as a Category 3 level load at 25Kpsi, deemed suitable in modern N-frame 44 Specials like the 624. The question is whether you want to use them and need that power. The guns are capable of handling it. It is at the very upper end of the power and performance envelope for the 44 Special. AA#7 is a better powder for mid-level loads, and AA#5 for standard level pressures.

{Please note that this was using a gas checked cast bullet and may not be suitable for a jacketed bullet where pressures could be higher. I recommend obtaining and reading those Handloader issues if you are interested in using such loads.}

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