"Hi Xavier! I've been reading your blog and thoroughly enjoying it. I find myself checking it everyday, and often sending links of your articles to family and friends. You've created a great mix of thoughtful observations and very useful information. Thus, first and foremost, thanks for your writing.Assuming there is not a recoil buffer in there, it appears to me that the pistol may have a barrel link that is too long for it.
I've recently been trying to get back into shooting after a much-too-long hiatus due to a myriad of factors. While recently shooting the Colt Commander that I inherited from my grandfather, the slide locked up on me. As you can see in the attached pictures, the barrel somehow got itself quite out of place, and the slide is stuck in a position that is not-quite fully retracted. When I pull back on the slide, it only moves about 1/16", and the barrel dips down ever so slightly. I can depress the recoil spring plug, but cannot turn the bushing. ANY advice you might give would be tremendously helpful! Of course, if you feel so compelled, feel free to talk about this in Xavier Thoughts."
I see two routes to take, the first is taking it to a competent 1911 'smith for evaluation and replacement of the link. The second route is to make certain the pistol is unloaded. Spray plenty of lubricant between the slide and barrel hood. Try to wash out the debris of shooting the gun.
Then, using the grip as leverage, press the back of the slide down firmly onto a stable wooden surface. You may have to put your entire weight on it. Hopefully the pistol will go into battery. If not, a smack or two with a carefully aimed rawhide hammer to the rear of the slide should do it. Be aware that you may damage the link or the slide stop.
Once the pistol is in battery, take out the bushing to give the barrel wiggle room, and retract the slide to remove the slide stop. Field strip the pistol and replace the link with one a size smaller.
Hope this helps a bit.