Well HS6 isn't too quick, and HS7 still slower yet. I would guess HS10 is even slower? Total guess. I can't see you're loading book, but is there a load for .410? If yes, how does it stack up against 296 data for .410?

Edit:
I found some .44 Mag data from the manual you posted. The charge weights are lower than AA9 significantly. 9.5-14gr vs 18gr for AA9. So I guess it's not all that slow.

Here's where I found snippits of data from your book.
1950s Hodgdon's BASIC loading Data Manual Vintage Reloading Manuals RETAIL PRICE | #1796082894