I'd been seeing quite a few of threads about slides being stuck back because the guide rod and spring had been put in off center so I decided to duplicate the problem and see how I could most easily fix the resulting stuck slide. Here's what I found. First off I was able to duplicate the problem twice and both times I was able to fix it the following way.
What causes the slide to stick? Reassembling the slide with the guide rod off center was what I did. The following pictures show the guide rod and spring as they should be put back in and the way it's put in to cause the problem. One side note: I tried this 5 times and was only able to get the slide to stick twice, so it doesn't happen all the time.
The correct way to put the guide rod on. Notice how the guide rod is in the center of the barrel lug.
Second picture shows the guide rod slightly off center, this is what caused the slide to stick. One note you can "feel" when the guide rod is off center because when you put the slide on and pull it back it has a mushy feel to it.
Grab the gun backwards (pic) and bang it in a downward and forward motion until the slide and frame light up.
You can then tell by looking at the barrel breech where the feed ramp is. You'll see where it has been pushed down below the locking block. Notice the feed ramp is under the locking block.
For me it took a couple hard taps on the slide to get it forward into position. Make sure it aligns with the back of the frame see below.
Once the slide and frame are aligned you will notice that the barrel is still down and the breech is not locked.
You'll also notice once slide is forced back to the normal place that the barrel and guide rod still stick out a bit.
After getting the frame and slide back to normal position just pulled the trigger to dry fire the gun and the slide will come of as in a normal disassembly.
Again it took a couple of whacks on the carpet to force the slide to align with the frame but once it was all it took to get the frame off was a trigger pull.