Vortex Defender-ST | Red Dot Redux Review

This article first appeared on AmmoLand News on May 14th, 2025, and appears here now with fresh updates.

I’ll admit I wasn’t a fan of the CCW-Defender from Vortex. It was a good optic, but it underdelivered. The auto shut-off required an insane 14 hours of stillness to shut off automatically. The refresh rate left a lot to be desired, and the battery life sucked. It held zero, was quite bright, and worked as a red dot, but I walked away unimpressed. Vortex recently released a full-sized dot as part of the Defender Series. Does the new Defender-ST outperform the Defender-CCW?

Diving Into the Vortex Defender-ST

Live Inventory Price Checker

	Vortex Optics Vortex Defender-ST 3 MOA Micro Red Dot DFST-MRD3	EuroOptic.com	$ 449.99 $ 299.00
	Vortex Defender-ST 3 MOA Red Dot Sight	GunMag Warehouse	$ 329.99
	Vortex Defender-ST 3MOA Micro Red Dot w/ Delta Point Pro Footprint - DFST-MRD3	Palmetto State Armory	$ 329.99
	Vortex Optics Vortex Defender-ST 6 MOA Micro Red Dot DFST-MRD6	EuroOptic.com	$ 449.99 $ 299.00
	Vortex Defender-ST 6 MOA Red Dot Sight	GunMag Warehouse	$ 329.99

Let’s start by addressing one of my biggest complaints with the Defender-CCW: the shake awake. Why must the gun sit still for 14 hours to turn itself off? Luckily, the Defender-ST ditches the 14 hours with a much more conservative 10 minutes. Leave the weapon sitting for ten minutes in total stillness, and the optic shuts off. Move it even a hair, and it fires back to life.

Vortex heard the criticism loud and clear, and I’m told this is the same with the Defender-XL. The Defender-ST uses a Leupold DPP footprint. Like the DPP, it’s a big optic designed for full-sized handguns. It has a 23mm wide window that’s 20 mm tall. A six or three-MOA red dot sits in the middle of that window.

The optic is 1.83 inches long and weighs 1.48 ounces. The Defender-ST features the same diamond-shaped texture on the front of the optic as the Defender-CCW. It’s textured and designed to rack the gun off walls, tables, boots, etc. Inside the optic sits polymer inserts. These provide an internal flex to help keep the optic running and from beating itself up.

Inside the Defender-ST

The battery changes out of the top of the optic. The battery life taps out at 25,000 hours. That’s lower than most on the market, but the Shake Awake helps expand that battery life. The optic has ten brightness settings divided into eight daylight and two night vision.

This Vortex Defender-ST uses the smaller 3 MOA dot. Bigger dots can be better for eye-catching close-range use, but smaller dots can be more precise. On larger handguns, I prefer smaller dots. Speaking of, I mounted the Defender-ST to my Glock 17. The Defender-ST has everything you need to attach to nearly any weapon with a DPP footprint.

The Vortex Defender-ST comes with a ton of different screw sizes for various guns, a convenient little tool, and a Glock MOS plate. I strapped the Defender-ST to my Glock 17 without any drama and was impressed that Vortex includes all the various screws with their optics. It even has a Picatinny rail adapter to run the optic on a long gun.

On Target

The Defender-ST uses 1 MOA adjustment graduations, and the turret feedback gives me a warm and fuzzy feeling. I can hear and feel the clicks. This feedback makes it easy to zero at the range when wearing Ear Pro and having others shoot around you. I zeroed the optic in with just a few shots fired and walked away pleasantly surprised. I like it when there is very little drama in zeroing my optics.

With the optic zeroed, I put it through a trial by fire. By fire, I meant throwing lots and lots of lead at targets near, far, and in between. I paid careful attention to the dot and worked my various drills. I wanted to see if the dot’s refresh rate was up to snuff. The Defender-CCW lagged and dragged with a noticeable blur as I transitioned between targets and went through a draw to presentation.

The Defender-ST didn’t have those issues. Driving the gun between multiple targets was easy. The dot doesn’t blur and remains a consistent little 3 MOA circle. I even used my phone to try and spot the tell-tale blinking, and it’s simply not there. Vortex fixed the refresh rate and the optic works without a hitch. Vortex revamped their mini red dots, and the Defender-ST is the product of a lot of revamps and reconfiguring.

More Than First Impressions

Beyond the basics, we get a workable red dot. The Defender-ST functions quite well. I could push it to the red line and blast through a long string of fire. The goal is to keep the dot moving and never to let it settle. A good dot doesn’t blink between shots. The goal of a good shooter is to make sure the dot remains a blur.

I’m an okay shooter, so I kept the dot a blur. There was no flickering or failure. The dot’s movement made it easy to track my shots and even call my shots when I went a little too fast for my skill level.

The big window made it easy to find the dot in odd positions, and the big window gave you a little bit of forgiveness. The view through the window is colored by a bit of blue. The notch filter is visible but not obnoxious. The little red dot itself is quite well-refined and easy to see. It’s an almost perfect circle. At close range, it’s big and easy to see, but at those longer ranges, it’s refined and easy to use at range.

Have you ever hit a ten-inch gong at 50 yards consistently? With some decent fundamentals and a good red dot, it’s surprisingly easy. I did that with the Defender-ST and felt quite proud of myself.

Keep It Steady

If you texture the front of the optic and tell me I can use it to rack the gun, I’m going to do that. I slammed this mother trucker against tables at the range, a sawhorse, and some simulated ‘cover’ I use at the range. It makes the fact I used the optic as a charging handle almost trivial.

What I hope wasn’t trivial was a few drops and falls from chest height. I dropped the optic on both sides and the top a few times. Yet, through all that abuse, the optic held its zero. Speaking of zeroes, I had zero problems with the optic.

Ultimately, the Defender-ST doesn’t do anything new or crazy innovative, but it’s a solid optic overall. Its MSRP is $469.99, but the MSRP isn’t street price. The Vortex Defender-ST tends to retail for less than $350. At that price point, I don’t need revolutionary; I need competent, and the Defender-ST is competent. It’s reliable, easy to use, and tough enough.

About Travis Pike

Travis Pike is a former Marine Machine Gunner, a lifelong firearms enthusiast, and now a regular guy who likes to shoot, write, and find ways to combine the two. He holds an NRA certification as a Basic Pistol Instructor and is the world’s Okayest firearm’s instructor.