61 Minute of Angle Zero Shift with Vortex Viper Red Dot Sight

[Mike S]

I decided to get a RDS for my Glock 19 a couple years ago, but didn't really put many rounds through it since it wasn't my every day carry gun. Other than using it for the DPS' First Responders Course, it was basically just used to familiarize myself with RDS'.

Last October I began training with it in earnest to prep for one-handed shooting in anticipation of support-side shoulder surgery in January, as I'd be in a sling for 6 weeks and a bit gimpy while doing physical therapy for the next couple months.

One of the downsides of the design of the Vortex Viper RDS is that you have to remove the sight to change batteries, but that critique isn't unique to this one, as the Trijicon RMR has the same design. I had anticipated a slight zero shift when remounting to the gun, but the three or four times I changed the battery the zero was still on the mark.

I assisted another instructor at his range in April, & we were doing a little shooting before his students arrived. His steel targets are set up at 25 yds, & I was missing by a wide margin low & right. The Viper RDS was zeroed at 36 yds, & I was accustomed to knocking down 6" plates at that distance. After I looked intently thru the sight, I could tell that the red dot was nowhere near aligned with the iron sights, so the RDS came off, & I've gone back to iron sights till it's replaced by something other than a Viper RDS.

That was in April, & I put off returning it to Vortex till now. I did a quick video last week to document how far off the zero had shifted, so I could clearly articulate the issue when filling out the return form. At 36 yds, the rounds weren't hitting the target backer; at 25 yds I was able to measure the shift from Point of Aim to Point of Impact as 16" to the 4 o'clock. That's a shift of a little over 61 MOA, and was a bit eye opening. According to a couple gun forums, mine isn't the only Vortex Viper RDS to lose its zero, but the other didn't specify how much theirs had drifted.

I'm quite certain Vortex will make good on it, but just a fair warning to anyone using ia Viper RDS as part of their EDC. It would be catastrophic to have to use it for self defense, and if beyond contact distance potentially miss your threat & put an innocent third party at risk.

[LabRat]

Wow, that's a lot of shift. Not drift; but shift.
Interesting information and a good video of the issue. You did not come off as bashing Vortex; just a presentation of your data and a path forward to resolve.

Like you, I've heard Vortex CS is excellent. Hopefully, they investigate to determine the cause, not just replace the sight and move on.
Having said that, a quick internet search didn't find more than 1 or 2 articles regarding Vortex RDS experiencing shift in the zero.
Maybe it's just a one-off and not a systemic issue?

I watched the video, but don't recall if you noted trying the RDS on another pistol? Just to see if the issue followed the RDS after swapping to another weapon? Any issue with accuracy when using the iron sights?
Just curious; weapon is also part of the "system" when you're shooting. Thinking out loud here....

I'm looking for an RDS for my Canik TP9SFx. Vortex was on my short list, but I think I'll hold off until you post a follow up to the results. Interested to know what they find as a likely or root cause.
A few years ago, I had an EOTech RDS that experienced a significant shift in the zero due to thermal drift. As I recall, humidity was also an issue linked to zero drift. Sent the 512 back to EOTech with the receipt and they did issue a full refund, including my shipping costs.
They were sued by the US Military for the issue as I remember.

Let us know what you hear from Vortex. Thanks for posting.

[Mike S]

Thanks for the feedback!

The G-19 is the only pistol I currently have that the Viper RDS fits on so I didn't swap it out, but I'm confident it was the optic & not the gun. I could look at the dot through the optic, and then refocus on the front sight & see how far off it was from the point of aim. After removing it & reverting back to iron sights the gun was dead on.

Vortex didn't say much when I contacted them, other than to send it in for repair & they emailed me a prepaid label for the return. The rep did offer to fill out the service request form for me, but I had already downloaded & filled it out. I did ask them to replace it with their new Defender-EDC as it's listed at the same MSRP, but we'll see. Regardless of what goes on it next, I'll be running it hard for a bit before I have full confidence it it.

It went in the mail yesterday, so I'll let you know when I get what I get back & how it runs.

[tk1700]

If your G19 has the factory MOS check out the Holosun SCS. It fits direct on the MOS mount so there isn't an adapter plate required. This allows it to be mounted lower. The battery is changed on the side so it can stay mounted when changing a battery. A great feature the Holosun has over Vortex is shake awake. When you pick the firearm up the sight turns on automatically. I'd never has an RDS on a carry gun that requires me to turn it on. I own multiple Holosuns (and VORTEX) and the Holosuns all have a battery life in excess of a year. When the battery gets low the reticle will flash. Also, Holosuns for pistols have the option for a 32 MOA circle and 2 MOA dot.

I sell both brands and Holosun out sells Vortex in the pistol category. I've seen 1 of each come back for warranty and each company took care of the problem quickly.

[LabRat]

Thanks for the feedback!

The G-19 is the only pistol I currently have that the Viper RDS fits on so I didn't swap it out, but I'm confident it was the optic & not the gun. I could look at the dot through the optic, and then refocus on the front sight & see how far off it was from the point of aim. After removing it & reverting back to iron sights the gun was dead on.

Vortex didn't say much when I contacted them, other than to send it in for repair & they emailed me a prepaid label for the return. The rep did offer to fill out the service request form for me, but I had already downloaded & filled it out. I did ask them to replace it with their new Defender-EDC as it's listed at the same MSRP, but we'll see. Regardless of what goes on it next, I'll be running it hard for a bit before I have full confidence it it.

It went in the mail yesterday, so I'll let you know when I get what I get back & how it runs.

Sounds good. Just my musing about the gun. Good check you did to confirm the optics.
Will monitor thread for any updates.

LabRat

[Mike S]

Well, it turns out that the glass had actually shifted a little bit within the housing of the Viper RDS, which in turn pushed the red dot askew resulting in the drastic shift in POI. I'm glad the Vortex Rep who called me actually took the time to look it over while we were on the phone, because the guys in the shop thought it was just zeroed way off.

I had been doing alot of one-handed shooting in the 6 months prior to the zero shift, racking the slide (by using the optic) against the holster, belt, pocket, jeans, etc, so I'm thinking that's what did it in.

Good news is that I asked them to replace it with the Defender-CCW, their newest RDS, & they did. Both RDS' are listed at the same MSRP, but supposedly the Defender-CCW is built more solid (and, the battery is top-loading so no need to remove the RDS to change batteries).

[puma guy]

Well, it turns out that the glass had actually shifted a little bit within the housing of the Viper RDS, which in turn pushed the red dot askew resulting in the drastic shift in POI. I'm glad the Vortex Rep who called me actually took the time to look it over while we were on the phone, because the guys in the shop thought it was just zeroed way off.

I had been doing alot of one-handed shooting in the 6 months prior to the zero shift, racking the slide (by using the optic) against the holster, belt, pocket, jeans, etc, so I'm thinking that's what did it in.

Good news is that I asked them to replace it with the Defender-CCW, their newest RDS, & they did. Both RDS' are listed at the same MSRP, but supposedly the Defender-CCW is built more solid (and, the battery is top-loading so no need to remove the RDS to change batteries).

[LabRat]

Well, it turns out that the glass had actually shifted a little bit within the housing of the Viper RDS, which in turn pushed the red dot askew resulting in the drastic shift in POI. I'm glad the Vortex Rep who called me actually took the time to look it over while we were on the phone, because the guys in the shop thought it was just zeroed way off.

I had been doing alot of one-handed shooting in the 6 months prior to the zero shift, racking the slide (by using the optic) against the holster, belt, pocket, jeans, etc, so I'm thinking that's what did it in.

Good news is that I asked them to replace it with the Defender-CCW, their newest RDS, & they did. Both RDS' are listed at the same MSRP, but supposedly the Defender-CCW is built more solid (and, the battery is top-loading so no need to remove the RDS to change batteries).

Hey,
Just catching up on this. Good to hear they were able to find the issue and solve it to your satisfaction. Not sure the rack procedure you're using is kosher, but I suspect it's not explicitly forbidden by the User Manual.
But it seems they were OK to replace the sight, even given the circumstances. Thanks for following up and letting us know.

LabRat

[Rafe]

I don't have any of Vortex's RDS products, but I do have a couple of their scopes. Super glad to hear of that kind of customer service. Maybe it's just me, but I hear of more firearm-related companies demonstrating decent customer service here in the 3rd decade of the 21st century than just about any other market segment.

'Course, with most large companies, trying to get through the automated answering systems just to speak to a human in Bangalore is enough to have you hang up...or throw your phone against a wall...which may very well be the plan.

I haven't switched to RDS for carry yet. Been seriously thinking about it. And one-handed slide manipulation is a consideration. Thanks for pointing out that out. Ya gotta be prepared to do that, and to me that means both a solid sight and mount...plus the sight needs to have a suitable front edge surface. When I first started looking around, that pretty much ruled out, for me, things like the SIG Romeo5 Compact and Primary Arms SLx Micro.

So, yeah. I'd absolutely expect a manufacturer of an RDS intended for a pistol to engineer and build for using it to rack the slide. Maybe not 10,000 repetitions of it, but still.

[The Annoyed Man]

Thanks for the update. Did they try to tell you not to use the sight that way again?

As well as a couple of Viper PST II scopes I have, I own an oooold Gen 1 Strikefire which is mounted to an M&P15-22 I haven’t shot in literally years. I’m sure it needs a new battery. That said, both of the magnified scopes came with a lifetime, no questions asked, warranty. I wasn’t sure if the same applied or not to their RDS optics.

I know that Primary Arms offers a similar warranty on all of their optics—of which I own 2 scopes, 2 of their newer micro reflex sights, and 1 RDS—because I’ve had a conversation with their customer service about it.

[Mike S]

Nope, the Vortex guy didn't blink an eye about racking the slide using the RDS, but I think it did vector him in to looking a little closer at the front of the sight whence he realized the glass had shifted just a little bit.

Racking the slide against the holster, belt, or something else sturdy enough to not give is pretty standard with one-handed pistol manipulations. Prior to RDS' being a thing, the technique taught was to catch the rear sight against something, but now that RDS' are becoming common the technique includes racking the slide using the optic.

The Defender-CCW was designed with a bit more bulk & a texturized/rubberized rim on the front intentionally for racking this way

Of course, you'll have to gauge if your equipment is resilient enough for that technique, hence my reluctance to use the ones Rafe pointed out (and the earlier RDS' from Vortex now that I've had this issue).

Putting together an instructional video on one handed techniques for my YouTube channel is on my to-do list, but I'm thinking it's going to be a month or so before I get to it. It'll be in conjunction with the couple thousand round stress test of the Defender-CCW so I can knock both out together.

I'm pretty sure all of Vortex's products are covered by their unconditional lifetime warranty, even their laser rangefinders. When my old Leupold range finder finally gave up the ghost I went with one of Vortex's for that reason; no other manufacturers seemed to warranty their LRFs beyond a year or two, especially the LED displays.

[The Annoyed Man]

When my old Leupold range finder finally gave up the ghost I went with one of Vortex's for that reason; no other manufacturers seemed to warranty their LRFs beyond a year or two, especially the LED displays.

I have a Leica Rangemaster 1200 that I bought in 2007 or 2008. I have no idea what Leica's warranty was like when I bought it, but I’ve never needed it. On their website, they currently say that their sport optics come with a transferable 30 year warranty.