Understanding Holster Retention, How To Test Retention, and How NOT To

Table of Contents:

• What is holster retention?
• Should a kydex holster click when the gun is inserted?
• Holster design and construction
  • Do PHLster holsters click?
• Testing holster retention
  • The wrong (but popular) way to test retention
  • The CORRECT way to test retention
• Is the "Shake Test" accurate?
• Weapon-mounted lights - light bearing holsters and retention

Holster "retention" means making the gun stay inside the holster when you need it to stay, while still being accessible for a safe and unobstructed draw. The gun should stay securely in place on your body without falling out of the holster, even through extreme movements such as jumping, grappling, parkour, or break-dancing. When your holster has good retention, you can bust a move with confidence.

In addition to holding the gun in, your holster must also allow the gun OUT on demand. It's important to have balanced retention - tight enough for security, but not so tight that you can't draw the gun when you need it. Your holster must allow you to get a clean, safe, and fast draw.

Retention for an IWB (inside the waistband) holster is accomplished differently than for an OWB (outside the waistband) holster. An IWB holster uses holster features + pressure from your body + pressure from your belt to retain the gun. This is different than an OWB holster, which uses only holster features and the belt. This article focuses on IWB concealment holsters only, so be aware that OWB holsters use different criteria for safe retention.

Few things feel more satisfying that putting your gun in a kydex holster and hearing that crisp, authoritative "CLICK" when it settles into place. But what exactly does the click mean, and what purpose does it serve? If your holster clicks, does that mean it's good? Or if it doesn't click, does that mean it's bad?

The “click” feel and sound is a feature of specific holster design features. On its own, it doesn’t tell you much about whether or not the holster is any good. A click can happen for different reasons, not all of them positive.

Basically, take the click sound with a large grain of salt. A clean, precise click without slop CAN mean the holster is made well. Sometimes. Or not. It can be hard for a novice to tell whether the click is coming from good design, or from sloppy work when molding and forming the holster. In any case, the click is only one factor out of many factors that are important in a well made holster.

Some holsters feel clicky because they are made poorly. For example, some holsters are molded with interference into the ejection port, which definitely makes a resounding CLICK sound, but also causes many other problems, such as excessive wear to the holster and to the finish of the gun.

Other holsters don’t feel clicky at all, but are well made and have excellent retention. The performance of the holster is what matters – not the click. Holsters are supposed to securely retain the gun when it’s worn on the body. Period. Whether or not they click is window dressing – it’s the job that’s important. The holster should retain the gun on your body through a variety of everyday and extreme movements (see the holster retention testing section).

When you test a large enough variety of good and bad holsters, you start to develop a sense for what good retention feels like. Whether or not the holster clicks, you want the retention to feel precise and intentional. It’s a feeling that’s hard to describe, but once you’ve handled some top tier holsters, you’ll know it when you feel it.

There are a few ways to accomplish gun retention when you’re making a kydex holster. For IWB holsters, the most common ones are friction and interference.

Friction is, well, friction. Friction between the gun (or light) and the holster shell holds the gun in place. The kydex squeezes tight around certain features of the gun (or light), and the harder the squeeze, the tighter the retention. Inserting a gun into a holster with friction retention feels gradual, and less like an abrupt click.

Interference is when the kydex is molded into a depression or void on the gun, most often the trigger guard. When the gun is inserted into the holster, the two halves of the kydex shell spread apart, and when they snap back together into the depression, you hear that distinctive “click” sound. The shape and depth of the indentation is a factor in how the retention feels and how “clicky” it is (though it’s not the only factor).

A holster can use a combination of both friction and interference fit – it doesn’t have to be purely one or the other. And one isn't inherently better than the other. They're both good when designed and implemented appropriately. Just know that most of the "click" sound comes from interference.

Interference fit. When the gun is inserted, you can see the two sides of the holster spread apart, then snap back together. That’s what gives you the “click” feeling and sound. Watch how the small indentation in the trigger guard causes this effect.

Some models do, and others don’t.

PHLster holsters are compression formed to tight tolerances, and every holster is test-fit before it leaves the shop. The decisive "click" you feel with our interference fit holsters (such as the Skeleton, PHLster Pro Holster, or Enigma Express) comes from precision along every contact point with the gun, not just the trigger guard. Our friction fit holsters (such as the Floodlight2) do not click, but they are secure, precise, and authoritative.  

There are good and bad ways to test holster retention. We’ll start by talking about how NOT to test a holster, then we’ll briefly explore how IWB holsters are designed to hold the gun between the body and the belt (or Enigma), why it matters, and the right way to test retention.

Contrary to popular belief, you shouldn’t test an IWB holster by shaking it upside down. The “shake test” is a popular internet sensation that you’ve probably seen before. To do the shake test, the user holds the holster upside down and vigorously shakes it. If the gun falls out, the holster “fails.” It’s a popular test because it’s simple and easy. As usual, though, the truth is a little more complicated and a lot less widely known.

The shake test makes intuitive sense. Of course you don’t want your gun falling out during vigorous movement, and shaking the gun seems like a good way to simulate vigorous activity. However, the shake test actually has nothing to do with the real-world performance of the holster.  That’s because holster retention alone isn’t what keeps the gun on your body when you’re actually wearing it. Many poor quality holsters will “pass” the shake test, and many good quality holsters will “fail” it. You can also manipulate the results of the shake test, as we’ll demonstrate in the video below.

Like many internet fads, the shake test is based on a grain of truth. When you gently tip the holstered gun upside down, it shouldn’t fall freely out of the holster. There should be some resistance, though how much can vary depending on the weight of the gun. Generally speaking, it’s reasonable to expect to handle the holster for routine activities (like donning and doffing, bathroom breaks, etc.) without your gun falling out, provided you use a reasonable amount of caution. However, there’s a world of difference between careful handling practices and shaking the gun upside down.

IWB holsters are designed to be worn between your belt (or Enigma) and your body. The pressure of your belt against the front of the holster provides inward force. Additionally, your body provides surface area, friction, and pressure on the other side of the gun, effectively sandwiching the gun in between two sources of pressure. This belt + gun + body pressure sandwich adds a ton of extra retention. It’s why you can do cartwheels, jump on a trampoline, or survive a car accident while wearing a well-designed holster – even though those things generate much more force than the shake test.

Two things about that concept are important. One, when you shake an IWB holster upside down, you’re missing the whole pressure part of the pressure sandwich. So your retention will feel much lighter than it would when wearing the holster. Two, if you try to adjust your retention to make it feel right in your hand, it’s going to be a lot tighter than necessary to accomplish the job of retaining your gun on your body, which can slow down or foul your draw.

In the video below, note how simply changing where you hold the holster changes the retention. Holding the edges of the holster allows the gun to fall out easily because no pressure is applied to the face of the shell. However, when you squeeze the shell where your belt would apply pressure, it makes the retention much tighter.

This video shows how you can manipulate the results of the "shake test" simply by changing where you squeeze the holster.

Since body contact is a big part of holster retention, and since all bodies are different, the most accurate way to test your holster’s retention is to wear it. That means putting on your holster and belt and unloaded gun (we recommend using a Barrel Blok for an added layer of safety). Get everything situated the way you plan to wear it in real life. Test retention by performing a range of activities, gradually ramping up the difficulty level as you are able. Jumping jacks, burpees, sprints, and hip bridging exercises are a great start. Make sure the gun stays in place through a wide range of extreme movements. (You may hold the holster in your hand and tip it upside down, but you won't learn anything of value by vigorously shaking it.)

When testing your draw, make sure your draw stroke is quick and clean, and that the gun releases from the holster crisply when you need it to. Use quick, confident movements. A slow or hesitant draw will often make your holster retention feel tighter than it really is.

For a great video demonstration of how to test holster retention, check out the “retention” segment in this video from Tessah Booth on her channel, Armed and Styled.

Most weapon-mounted lights are wider than the trigger guard of the gun, which means using interference fit around the trigger guard won’t work. If you tried, the light wouldn’t be able to pass through the gap. In other words, the entire lower half of the holster needs to be wide enough for the light to fit, so molding around the skinny little trigger guard won’t cut it.

Instead of using the trigger guard for retention, many light bearing holsters use the light itself for retention. Again, two types of retention are possible – friction and interference. Friction fit is when the kydex is fitted tight to the light. The amount of pressure on the light determines how tight the retention is. Your belt and body still play a major role, so make sure to test retention as the holster is worn.

With lights, interference fit is sometimes possible, but not always. It depends on a) the shape of the light, and b) whether the holster is made for one specific gun, or if it’s made to fit the light and accommodates many guns. If the light has a shoulder or depression where you can mold in some interference, you can sometimes get a “clicky” effect when molding to the light. But that’s impossible with some lights, and they are friction fit only.

If you’ve made it this far, you know more about holster retention than the VAST majority of gun owners. Most folks never learn this level of detail, but it does make a difference. Next time you hear someone say their gun fell out of the holster, or that their draw feels slow and sticky, you'll know exactly how to troubleshoot the problem and help them be successful.

We hope you will use your knowledge to teach others who are not as far along on the journey. Your time is valuable, and we appreciate you spending it with us!

Jon and Sarah Hauptman, Owners, PHLster Holsters

Photo by Tamara Keel