Try a faster powder . I bought Acc #5 with the hopes the burn rate would be close to Unique , which is great for mid-range loads but you can't light load it ... low pressure = poor combustion + filthy loads . Working with it and 38SPL HV supplying some load data he chronoed , has shown Acc #5 to be a good deal slower and best regulated to at least +P loads and Magnum loads .
If you can try some powder with a faster burn rate ... it should help .
I tried for years to load target loads with Unique ... it just won't work ...wrong burn rate and no way to get around it . A can of Bullseye opened my eyes ...700X , Red Dot , W231 , HP-38 ...all will give you better results !
Gary