I don't know what bullet was tested, but the 2004 Alliant manual shows the following max loads (reduce accordingly for start) for a 260gr JHP in .45acp.
Bullseye 4.5gr, 725 fps, 19.4k psi
Unique 5.4gr 760 fps, 19.4k psi
Herco 5.9gr, 750fps, 18.6k psi
Blue Dot 8.3gr 780 fps, 19.0k psi
Of those, I'd probably try Unique first. I've taken every effort to type correctly and proofread, but please verify the data before use.
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