Sounds like not enough taper crimp..Have you done the "plunk test" to see if your rounds chamber easily?
Here's how to open a 1911 when this happens.
Point the gun downrange. Support it with your left hand- and release your right hand from the gip, but keep the web of your right hand under the beavertail. Now move your right fingers up over the slide. Your thumb is under the beavertail, and your fingers are wrapped over the top of the slide.
This position give you tremendous mechanical advantage. Close your right hand hard and if necessary, mirror that hold with your left. The round will break loose- try to keep the slide from closing again, and clear it.
If your range has a vertical non marring surface, you can push the edge of the slide at the muzzle- ours had some carpeted uprights that were perfect for that.