I'd like to resurrect this thread and get updated opinions, by either the original participants and/or others who would like to chime in.
This is a subject I never considered for at least the first 10-15 years of owning guns and keeping semi-autos loaded at home or on my person for self-defense. In the more recent past few years, after doing a lot of reading on the internet, attending a CCW class in a new state, etc. I have been seeing and hearing a lot about it.
I currently rotate my carry ammo regularly and take steps to remediate the risk of bullet setback.
For example, if I have un-chambered and re-chambered a round more than once or twice, I pull it out of rotation and stick it in a separate box for use at the range.
As a matter of practice, this only happens maybe every 1-2 months. I never unload my carry guns without a reason, like to clean or inspect them. I have a second P-07 that I use for dry fire so I don't need to unload my primary carry gun for that. I prefer to load them and leave them loaded and secured. I don't even press check them. If they're in a carry holster, in my lock box or on my person, I know they're loaded.
I also dump my carry mags at the range and refresh them with all new ammunition every six months or so.
The thing is, I go through the motions of doing this, with no personal experience of having ever experienced a problem with my carry ammo. In fact, I never used to even hear about it from people who I considered knowledgeable on the subject of guns and self-defense.
In a previous life, I attended a CCW course taught by Tom Givens. At the time he was just a knowledgeable guy who owned a local range and taught CCW classes. I attended the class with some guys I worked with who were also getting their CCW licenses. Now he is widely regarded in the industry as one of the most knowledgeable people about self-defense shooting incidents, and has a nationwide training and certification program. I can tell you I recall him talking about issues of gun safety, issues of carelessness like accidentally bringing your gun through airport security, many scenarios of crime victims shooting offenders, why you should always keep your gun on your person, about washing the lead off your hands after shooting, even advising me on my grip and gun selection when I was qualifying on the range, but not a single time do I recall him talking about rotating ammo or bullet setback.
The more recent CCW course I took in a different state, the instructor spent a lot of time talking about rotating your carry ammo.
Then I see articles on the subject around the various gun-related websites, then comments underneath saying that is just a myth that exists on gun forums and nobody ever has an actual problem with it.
I think back to when I had no idea what "bullet setback" was and how many times I must have un-chambered and re-chambered my weapon with the same cartridge. Also how it used to sit locked up in my car during extremes of heat and cold, how some of that ammo was kept around for 10-15 years and the copper had oxidized to being totally green, yet I have never had a single failure out of any of that carry ammo that I could attribute to bullet setback or being old.
Then I see threads like this one with respected members who work in law enforcement and have seen practices like repeated shift-change un-chambering and re-chambering cause bullet setback to happen on a regular basis.
Anyway I feel like I am doing the right thing with my ammo currently, but I wonder what the current opinions and practices of others are.