Blacktail53,
You can, but whether it works correctly or not depends on how firmly the case neck holds the bullet, and how hard the firing pin whacks the primer. Generally find it much better to have the chamber correctly cut for a crush fit on new brass, or to neck up and then neck down again to get a crush fit.
These days, however, I find the easiest solution is to use a factory round that produces the desired ballistics. There are so many out there these days, especially those with steeper shoulders to begin with, that I really don't see any point in fooling with "improved" cases.
