eman308, The AA#7 is a good powder but...it is a little fast for the heavier bullets. Here is some data for Accurate Arms as you can see 1200fps is a little out of reach velocity wise. No. 9 will get you closer.
That being said the upper loading of AA#7 is not athe rocket you are looking for but that pressure will go up quickly above the recommended max shown. Good luck!
HDY 200 XTP 1.250"
No.2 5.7 916
No.2 6.3 1041 36,700 psi
No.5 7.0 938
No.5 7.8 1066 35,100 psi
No.7 8.8 960
No.7 9.8 1091 36,500 psi
No.9 11.3 1030 No.9 12.5 1170 37,000 psi