Hay Ken: How ya be?? Ummmm, about that 8.6 gns of Unique - I'm not so sure. I think that sounds just a bit 'hot' - as in 'hot', not just warm. I can remember busting primers with 8.5 gns of Unique, so I would be a bit careful were I you, ol buddy.
About the highest I've ever gone with Unique and anything over 200 gn in the 45 acp was to 7.2 gns. Although I like Unique, I have found the VihtaVourhyOy powders to give me higher velocites and lower pressures. I've been using them for a while now. But, 7.0 gns of Unique behind a 200 gn 45 acp slug should be an easy shooting load from a full length Gov't Model but might be a bit snappy from a shorter version, like yours.
Typically, 6.5 gn of Unique behind a 230 gn ball is supposed to get you the mil-surp velocity of 877'/sec, as per the old Lyman manuals, but from a 5" Gov't Model. I think your Springer has a shorter bbl, but under a 200 gn bullet that load should give you no problems and be fairly comfy to shoot.
Anyhow, I do not think your load of 7 gns of Unique over the 200 gn ball is too hot for a hardball gun. But again, I always stuff all my 45s with 22 lb recoil spring kits from Wolff - they work wonders and you need not worry about frame battering with heavy loads.
My friend, I would like to suggest a Lymna manual, one of the older ones if you can locate a 43rd or 45th edition, and one of the newer VihtaVourhyOy manuals and some of their powder - you just might like the change and the way they treat your 45. Hasta Buddy. Mikey.