Be sure to use a nice bulky powder. If you drop the speed that low you could get to a point where the low powder charge could result in a large boom. Imagine the primer lighting and causing 2 ignition points inside the case. 2 flame fronts, or pressure waves, slamming together in the case will cause an amplification, pressure spike, and very easily rupture a case.
Sounds like a job for Trail Boss powder. According to Hodgdon's load data site 180gr & 200gr can be loaded to 130PF with Trail Boss.