If you’re constantly making trips to the range…
I’ve never measured my carry rounds to see how much setback, if any, has occurred from repeated chambering of the same round. I generally only unload when something goes in the safe or to the range (to replace with FMJ) or for cleaning. For that reason I don’t worry too much about it … and I when I do reload my carry ammo I usually strip the first couple of rounds off the mag and mix them up.
My only experience with real setback was in a recent 1911 Operator’s course with Larry Vickers in ATL. During a string of fire my pistol stopped making the BANG noise. I tapped, racked, but still no noise. I looked down through the ejection port with the slide locked back and saw a round was sort of lodged, nose down in the mag causing it not to feed. LAV was standing right beside me so he actually took my pistol and pulled the mag out to see what was up. He let loose a couple of fun words then removed the offending round manually and handed it to me. The bullet was set back prob half way or more. It was freaky looking. NO idea if it looked like that when I loaded it into the mag or not. I was feeding loose rounds from my pocket into partial/empty mags between strings of fire and might have loaded it up without even looking down at it. I also picked up a few live rounds off the deck and stuck them in my pocket. We were ejecting live rounds setting up ball and dummy drills, etc. and I might have picked it up like that … someone else’s trash.
Setbacks seem to be a function of pistol design, caliber, and case material.
Some pistols have a steeper feed ramps, and steeper feeding angles when stripping off the magazine. This causes more pressure on the cartridge to be loaded.
Calibers such as .357sig have a very small crimping area, and are prone to setbacks. The most solid crimps are usually with straightwalled cases like the .40S&W and .45acp. The 9mm has a tapered casing and less grip towards the rear of the bullet. Some companies like Federal Cartridge will put a cannelure on the casing to increase case friction and help prevent setbacks on the 9mm.
Aluminum cases don’t have a very tight crimp, and thus are prone to setbacks. Steel cases will sometimes have a weak crimp too.
I don’t rechamber except when cleaning and not always then depending on where/when I clean it.
The round in the chamber is fired whenever I go to practice as my very 1st cold shot.
This has several benefits:
-I don’t keep rechambering rounds
-I don’t keep defensive ammo sitting in a magazine forever going through heat cycles potentially degrading the powder/primer
-It lets me see where I that 1st critical shot would be with my actual carry ammo drawing from concealment
-It gives me the reason to go to the gun store to look at cool toys when I start to run out of carry ammo:haha:
-It keeps me somewhat on the cutting edge of ammo development instead of still using Winchester Silvertips that I purchased back in 1997.
To me, the extra $ it costs me to fire off that 1 round of carry ammo each time I go to shoot is more than outweighed by the benefits.
I am a civilian however and the only time I unload my G19 is during firing and cleaning.
That’s certainly a straightforward solution.
I think it’s safe to say:
You want to rotate your carry ammo (rounds you’ve chambered plus probably shooting it all and buying new stuff) somewhere between (a) every time you touch your gun and (b) never. Where you lie along that spectrum depends on your carry habits (cop unloading every day vs. civvie unloading every range trip vs. nightstand gun that gets shot twice a year).
It’s probably wise to pick a method that works for you (rotate your chambered rounds every few times, shoot the chambered round each time, ignore it and shoot all your ammo up every 3 months, whatever) and, if anything, err slightly on the side of caution. After all, the amounts we’re talking about are a few cents or dollars here and there and the subject is: things that could save you or your family’s lives.