I've actually found 9mm to be an extremely easy catridge to reload. No possibility of double charge, works great with faster burning powders, good brass life, lots of good load data, etc.
I find it easier to crimp in a seperate step using a crimp die, so my experience is based on that, but should still help some with your problem. The seater die does not need to be set to crimp in order to remove the bell in the case. Overall length is often more unifrom when seperating the two actions.
I crimp FMJ bullets just enough to make a very slight mark on the jacket. The die touches the case and I give it about a 1/2 turn for a light crimp (barely marks the bullet), that's usually enough. A full turn is maximum crimp.
Others will measure the crimp at the case mouth and compare that to a case that is not crimped. Say .001-.002 for a light crimp and maybe .003 for a heavy crimp. I don't typically need to measure mine so precisely.
I've used a medium crimp to prevent setback when using plated bullets being careful not to cut the plating.
If you're deforming the bullet into a coke bottle, that's definitely too much crimp. Pull yours and visibly inspect.
My recommendation for the 9mm is Alliant Power Pistol. It meters well, is useful in many other cartridges, produces excellent velocity in 9mm and is accurate. It does create some flash, but my reloads are just practice rounds, so it's not a negative for me.
Last edited by testuser; October 10, 2012 at 10:32 PM.