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I say check your crimp. When using the slower powders hard crimping is needed for good start pressures that as close to the same with each other as can be had. Your crimps should be at the point of not quite buckling the case, just almost. That will also help with a lot of the unburned powder. If there is just a tad bit of powder, and everything else is working shoot them.
Though I am going to say try crimping a tad bit more. You may have to sacrifice a case, and bullet or two to get it right. Oh and make sure your brass is trimmed to the same length to get a crimp in the same spot with each one.
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That is bad advice and you putting it to the point of crumpling the case is very problematical.
You should only crimp enough to achieve the mission and in some cases, that means none at all.
That has been tested and the crimp has no affect on the combustion process, situation or velocity. Red this.
http://www.realguns.com/Commentary/comar184.htm
If you read the reload manuals, Sierra tells you to use a firm taper crimp a 9mm , Hornady says mild or none. Crimping a 9mm too much can lead to issue with head space as it head spaces on the mouth. All you want is for the bullet not to move when its cycled and a very mild does that just fine.
I do have a Speer JSWCHP that does require a crimp due to the bullet design (no longer made but I have lots). I do crimp but also have shot it sans crimp and not an issue (the crimp may keep it safely away from occasionally separating and I accept that).
Raunching on your cases to the edge of failure for no good reason is very very very bad practice as you can push it into other failure modes as well as hard on the brass.