Bullseye has long been a popular powder for pistol target loads but probably a bit scarce these days. I use Winchester Super Target for .38 Special, 9mm and .45 ACP. For my 10mm I use Winchester Super Field which is probably better for the .40 S&W. The Winchester powders are very clean burning and are fine ball powders that meter perfectly through all measures. I think Bullseye will be a bit fast for the .40 unless you have very light loads.
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