What brand/model of bullet? H&G 68, Lyman, Lee, Zero, Barry's?
Here's what a loaded Lyman 452460 200gn SWC should look like. Taper crimp, .470" at the mouth. If it won't chamber, then see if the bullet is hitting the end of the chamber. Remember, the 45acp head spaces on the case mouth. Too much crimp and it won't properly. Not enough, and it might not go in. Build yourself some dummy rounds until you get what works. Get with a buddy that's reloaded 45acp successfuly to show you.
-Steve