Yondering, Yes, 5" barrel, 1325 with 200's is smoking, sounds like a very serious load with the 6.5" barrel, I thought about some 200/220 hardcasts for later on.
The forum won't let me edit my post above, but I shot some of those loads over the chrono again this weekend and realized I misremembered; they actually do an honest 1350 fps avg from the 6.5" longslide. Velocity from the standard barrel length is very similar to your load though.
If you're going with hard cast, I really recommend sticking with 200gr, the heavier 220 gr bullets just take up too much capacity in the 10mm and restrict it down to little more than a small bore +P .45 Auto. You'll get all the penetration you might want from a 200 anyway, and the extra velocity is a good thing. That 200gr Mihec mold I pictured above is about the best design you can get, if you can find one; you get the option of a solid WFN, or shallow or deep hollow points, to tailor the bullet for your needs.
