Yeah I had thought about that but I am doing further Research. Looks like W296 does not have a flash suppressant. Alliant BE-86 does and so do several of the Accurate Arms powders. #7 may be a good choice since its faster than #9 which does have a suppressant ( I noted it was not as bad as W296 but the 7 1/2 inch barrel does not help in this respect. Note this is for the blackhawk with 90 grain XTP and I can load down plus #7 is a faster powder and it does contain suppressants.
If you want to do some sleuthing on your own, go the the manufacturers web sites and read their MSDS and look for potassium nitrate, Potassium Sulfate, and Potassium Carbonate used as a flash suppressants. A side effect is a reduction of flame temp ( might help with flame cutting ) and no noticeable effect on velocity, but a slight increase in smoke.
Hodgdon makes it difficult to determine which of their powders contain the suppressants since they put a lot of their powders on a single MSDS and listed the items as 0-3%, meaning some powders do not have it. ( looking over some old data I would venture a guess that many DO NOT.)
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