I was shooting prarrie dogs today at 350-400 yards with my 223 and PST 6-24 SFP scope. I was unable to get a clear scope picture with my magnification turned up past 12. I tried using the sunshade, waiting for the barrel to cool (hoping to eliminate heat from mirage), nothing worked.
It was the first time I have shoot the scope at these distances. I have however used the scope at at 24x before on a 100 yard range and found the eye relief difficult to manage. I needed to move my eye closer to the scope to get a scope picture at all with the magnification turned up past 12. Shooting on a 100yrd range, once I adjusted my position the optics clarity seemed fine. However at longer ranges clarity at high magnification is bad.
I would expect these high magnification clarity issues from a $100 scope, but the Viper PST, with its excellent reputation and costing $750 I expect better performance.
What do folks think? Does this sound like a mechanical issue and I should send it in for warranty repair?
That model PST is known for having fairly good glass (for its price). Questions:
What were the weather conditions? Mirage can be a big factor at 300-400 yards. Hot weather, bright sun, or even cold air + bright sun + wind will do it. Although barrel heat can cause mirage, mirage can also come from air anywhere between your scope and target, even if the barrel is cold.
Did you adjust the ocular (reticle focus) carefully? If it’s not quite right your eye may be able to somewhat compensate at lower magnification where the target image is in focus through a wide range, but not at higher mag where the target focus is a narrow range.
Similarly…
Did you adjust the parallax (side focus) for best focus? The markings on the knob are a very, very rough guide and are generally not quite right (or sometimes way off) on all brands and models of scope, for reasons inherent to scope design. You need to adjust it by eye for best focus, then check for elimination of parallax - because in some scopes best focus and zero parallax aren’t in the same place.
Personally, I’ve never understood the popularity of Vortex.
I’ve never owned one, but I’ve looked through plenty of them, hoping to be impressed enough to purchase. The quality of the glass turned me off, even at low magnification. I’d take a stodgy ole Leupold any day of the week even if it meant living with a non tactical reticle and capped turrets.
I think what you are experiencing is typical of lower mid range quality glass.
I won’t rule out something being wrong with your scope, its just those are some of the sacrifices made to hit a price point.
It was in the 80’s and sunny. Typical for Colorado this time of year, with light consistent wind. We have had a lot of rain here over the past month. Much more than normal. The sun had been out and shinning bright for 4-5 days now (normal weather). I dont know much about the weather or atmospheric conditions that contribute to mirage but the conditions we had, feel like there may have been a lot of moisture coming out of the ground, which to me a least, make sense as a cause of mirage.
Yes I tried adjusting paralax
Yes I tried adjusting ocular focus
A Vortex rep said it sounds like my scope is too far forward, this also makes sense because I shoot it at lower power most of the time and had it mounted accordingly. This offers some explanation… I think what I was experiencing was a combo of mirage and the scope being too far forward.
Obviously the scope placement is an easy fix. What can be done about mirage?
Not much. Mirage is an issue of the atmosphere and you can’t control it. You can reduce the effect by reducing magnification. You can avoid mirage by shooting in early morning or near dusk when it tends to be a lot less.
Be sure to play around with both focus controls some - I’ve been amazed at the scopes that I once thought had mediocre glass that actually just needed proper focusing.
There’s a wide range of glass quality in the Viper PST line, based on my personal experience. The 2.5-10x44 (SFP) and 4-16x50 are generally dogs - very poor clarity at max magnification (or 13x and up in the 4-16x). The 2.5-10x32 FFP has much better glass. The 6-24x50 has pretty decent glass, as long as you aren’t expecting too much. None of the PST scopes are my favorite, but some of them are OK.
The PST was a great set of features at a price when it came out. It’s been surpassed now and is due for a new model replacement. I would bet on seeing that in the next year.
Vortex makes scopes at all price and quality levels. Their Gen2 Razor seems to be world class, and the Gen1 Razor was very good. Their $100 Chinese scopes are what you’d expect. Personally I like their Razor line and nothing below, but I can probably be accused of being a glass snob by now.
The Bushnell Elite Tactical 3-12x44 and 6-24x50 are price competitive with the PST and offer better glass and build quality, and a better reticle in some models (the G2 DMR reticle). However most versions don’t have illumination, although the BTR-MIL reticle does. This series is made in Japan and feels like it. That would be the close competition that’s been around for a while.
More recently, Burris has revamped its XTR scope line and moved production from the US to the Philippines. The XTR Gen2 is probably the most direct competition for the PST in price, features and target market, and I would say it’s better in all respects but slightly more expensive, depending on the models being compared. Burris also has a similar lifetime, any-owner, somewhat no-fault warranty. Vortex probably has the best warranty, either compared to other brands or compared to anything you can reasonably call a warranty.
I’m running a 6-24x50 Viper PST and couldn’t be happier with it. It has great glass given it’s price point. It’s no Nightforce or US Optics, but it’s also nowhere near the cost.
I recently had mine out to 720 yards and snapped a quick pic through the scope. This is at 24x magnification around 1 PM on a sunny, 80° day. The blurriness / lack of sharpness you are seeing in the picture is 100% mirage. We got out there earlier in the day and the target was pretty clear with the lack of mirage due to the lower temperatures.
That photo is pretty consistent with my experience. I was shooting at a shorter distance but at prarrie dogs: a target more difficult to acquire. The conclusion I have arrived it is that I really don’t have enough experience to determine if the problems I experienced are due to mirage or optics quality. I am however leaning towards mirage. It will take a few more outings with different environmental conditions before I will have the basis to make an intelligent judgment.
I own the 3.5-21x50 in two flavors, the original DMR and the newer ERS. I’m not sure if they have identical glass or minor changes on the newer ERS. Both of them have excellent glass, with minor caveats. Resolution is excellent and there is very little chromatic aberration (color fringing). They are not as bright, in terms of perceived light transmission, as many scopes in their price range. This is probably a design compromise to get the 6x zoom range - more lenses are required. Also, there is tunneling below 5x, so the bottom end of the magnification range is of limited usefulness (it reduces magnification but doesn’t increase the field of view, so there’s not generally a reason to use it). Practically I treat them as 5-21x scopes, which is a good range but barely more than the 4x zoom range of many competing scopes.
However, those Bushnell scopes shine in two aspects - value for the money, since the DMR version can be found for a little over $1000 with some shopping around, and adjustments, which in various other people’s carefully documented tests have repeatedly been exactly dead on. You would think all scopes over $1k would have perfect adjustments, but the same tests show that a lot of scopes in the same range wander a bit from the indicated adjustment values.
I haven’t owned the 4.5-30 (XRS). Reviews I’ve read seem to say that it’s merely good, not great, in the glass quality. Mechanically I expect it’s the same as the DMR/ERS.
