[CourtJester]

I've just started loading 9mm and .45. I'm using Accurate #7 powder with winchester magnum pistol primers. They fire okay but leave behind what looks like unignited powder.
What and I screwing up here or is this normal?

 

[potentialglock]

Why are you using magnum primers? That's your first problem. Neither caliber is a magnum caliber so basically you have the wrong primer. Don't quote me on this cause I might be wrong. But magnum primers burn slower, hotter and in some cases send burning shrapnel into the powder to help ignite it. Some of that residue could be from the primer. Switch to small pistol primer for 9mm and large pistol for 45. But no magnum. Not enough powder in either cartridge to need it

 

[Overkill0084]

First, I have not used AA#7 ( I Like AA#5 though)
But if it's like some other powders (2400 comes to mind), it sometimes takes a fair bit of pressure to eliminate unburned powder. It doesn't help that .45 acp is fairly mild mannered as far as pressure is concerned. Unless it gets crazy it's nothing to worry about. You could warm things up some and it may help.

Why are you using magnum primers? That's your first problem. Neither caliber is a magnum caliber so basically you have the wrong primer.

These days, Magnum LP primers may be all that's available. While they are a bit of overkill, there really isn't much in the way of danger as long as typical cautions are observed, e.g. work up your new load accordingly. I believe that I read somewhere once that Mag Primers are about the equivalent of an additional tenth of a grain of powder (Rule of thumb/Wild Assed Guess kind of thing). Don't know if it's entirely correct, but it sounds somewhat plausible. Whatever the case, it's certainly enough to be accounted for.