Bullet Setback And Three Ways To Mitigate It

Bullet setback is where the bullet gets pushed deeper into the cartridge case, usually from being chambered and extracted repeatedly. It’s a common phenomenon with concealed carry guns and police duty pistols, as they get loaded and unloaded with regularity. 

It’s something you need to watch for and – if possible – avoid, as it can be dangerous. It’s precisely why it’s recommended to rotate your carry ammunition, but – if you know a few tricks – it’s possible to not have to. 

Bullet Setback Can Create Dangerous Conditions

How setback happens is the bullet itself contacts the feed ramp, which pushes on the bullet. Object in motion vs larger object that is not, and so on. Eject and rechamber the cartridge more than once, and eventually, it can get pushed past the crimp. 

The more times a cartridge goes up the feed ramp, the more likely it is to happen, and it’s a possibility in any firearm with a feed ramp and a non-heeled bullet. Shotguns and revolvers, of course, are immune. 

If you find a bullet that has been set back, throw it away. Don’t fire it. 

Firing a cartridge that has been set back can create a dangerous spike in chamber pressure (case rupture is very possible), which can lead to a catastrophic failure and potentially serious injury.

So…how do we avoid it? 

Rotate Your Carry Ammo…If You Can Afford To

If you’ve chambered a JHP or JSP (in a rifle) more than a time or two…pull it out of your mags, put it in a bucket for range use, and shoot it if setback hasn’t already occurred. Some experts recommend never chambering a cartridge more than once. 

But…the reality is quality JHP (or JSP) is not cheap, and most people do not have the budget (whether it’s a civilian or an agency) to constantly shoot up Gold Dot or HST or what have you at $1(+) per trigger press. 

So while rotating out carry ammo is optimal, it’s not necessarily feasible for everyone. So here’s two administrative loading techniques to avoid setback. 

Chamber Port Load

Here’s a technique for a chamber port load that Riley Bowman from ConcealedCarry.com has demonstrated a few times on social media and elsewhere. Be sure to always orient the pistol in a safe direction; the rules of gun safety always apply, including and especially during administrative handling. 

You start with an empty gun, and lock the slide open. 

Drop the cartridge into the chamber. Hold the slide with the support hand, actuate the slide release, and slowly ride it forward until it stops.

Tilt the muzzle upward and slowly pull the slide back until the cartridge starts to slip out. Keep going until the rim goes past the extractor. 

Let the slide go forward, capturing the rim and chambering the cartridge. Then put the pistol very carefully into the holster and top it off with a magazine. 

This method works for almost all centerfire semi-auto handguns, including 1911 pistols and their pesky internal extractor. However, it doesn’t always work with subcompact pistols (including the Glock Slimline models, even the 48) as they have a shorter chamber port than full-size and compact service guns. 

Loading From Field Strip

The other method is to load the chamber of a field stripped slide. This works with any Browning system gun except a 1911, but anything else – Glock, CZ, S&W M&P, whatever – is fine. 

After taking the slide off the frame and removing the recoil guide rod/spring assembly, turn the slide over and move the barrel out of the way. Push the rim of the cartridge into the extractor until the rim is captured. 

Slowly push the barrel back into battery until it has fully seated, and replace the recoil guide rod assembly. Then, put the slide back onto the frame, and – for striker-fired pistols – pull the slide back just enough to reset the trigger.

Safely holster the gun, and top off with the magazine. 

So…if you don’t want to literally throw ammunition away, that’s how you can chamber and rechamber carry ammo without worrying about setback.