Optics have evolved significantly from the basic variable power optics and first-generation red dots developed in years past. Today, there is an incredible lineup of optics available, ranging from basic red dot sights to high-power variable optics with complex reticle patterns. However, somewhere in between these optic types lies another popular option.
Often overlooked, prism scopes are an incredibly versatile optic system that blends features of both variable power optics and red dots. Prism scopes can be optimized for various applications, from simple recreational shooting to competition, duty, and hunting.
Prism scopes have found extensive use among militaries and law enforcement groups, with popular models like the Trijicon ACOG serving for many years. Despite their prevalence, there are still many who lack sufficient knowledge about them. We aim to address that gap by exploring what prism scope to consider when choosing one, and factors to keep in mind before adding one to your rifle.
Understanding Prism Scopes
Unlike rifle scopes, which use two lenses at both ends of the housing, a prism scope employs two prisms to physically shorten optical paths by folding the light within the optic. While variable magnification isn’t possible with this style of optic, they tend to offer a wider field of view, a clearer sight picture, and fixed magnification, depending on the optic chosen.
Prism Scope Advantages
Prism scopes offer several advantages, starting with their compact size and reduced footprint compared to variable power optics. While variable power optics can be bulky, prism scopes tend to be smaller and lighter. It’s essential to note that the size of a prism scope varies based on its magnification. For instance, a 1x prism sight tends to be much smaller than a 5x sight.
Additionally, prism scopes are known for their rugged reliability and shock resistance. With fewer moving parts than variable power rifle scopes, the risk of damaging key components is reduced. While this doesn’t imply recklessness in handling, it ensures the optic’s durability in harsh conditions.
Additionally, prism scopes tend to provide a clearer picture. We touched on this previously, but it’s important to keep in mind if you’re considering getting a prism optic. Compared to red dots, prism scopes are better for enthusiasts with astigmatism; they offer better light transmission without blue tint and provide a better reticle image as a result.
Another key feature found in most prism scopes is reticle illumination. Most prism scopes are illuminated. This makes your sight picture much easier to quickly acquire your target and much easier to see in brighter conditions. Also, since prism scopes use etched reticles, the optic reticle is still visible when not illuminated. Even if the optic’s battery dies, the etched reticle remains visible, distinguishing prism sights from red dot sights prism scope unusable in similar scenarios.
Between variable power optics and red dots with magnifiers, there’s often a lot to consider. Fortunately for you, our guide on LPVOS vs. red dots with magnifiers breaks down both options.
Factors to Consider when Choosing Magnification
Like we said before, prism optics have fixed magnification, so there are a few key factors to consider when shopping around for an optic.
Depending on the model optic you look at, prism scope magnification tends to range anywhere from 1x to 5x and 6x magnification. Different applications require different magnifications. For example. If you were competing in a close-quarters carbine course, a 1x magnification would be more useful than a 5x or 6x sight. Outside of personal preference, you’ll need to consider your rifle’s purpose before selecting a magnification.
Different Magnifications for Different Purposes
For competition and in duty applications, it’s better to have lower magnification since targets are usually within 10-50 yards, though even at 100 yards it’s more than possible to accurately hit a target with that magnification. For hunting, where shots may be taken at distances of up to 150+ yards, higher magnification proves beneficial.
For the uninitiated, an optic with a higher magnification may seem like the better option since you’ll be able to see a closer image of your target, but in the wrong application, it can hinder your ability to properly use your rifle.
If you’re wanting a magnified optic but worried about the magnification negatively affecting your speed when acquiring targets, 2x-3x magnification is the sweet spot. With these magnification levels, it’s generally easier to shoot both eyes open, but keep in mind that this is different for every enthusiast and your results may vary. Ultimately, it’s about finding the balance between your optic’s field of view, eye relief, and overall size.
Something we want to point out is how different 1x microprisms are compared to other magnification levels. Unmagnified prism optics have different properties compared to their magnified counterparts. 1x prism scopes function more closely to a red dot sight and are often used to serve the same roles. They often have a more forgiving relief, making them just as fast as a red dot sight for target acquisition. Our guide on the 5 things to know when buying a red dot highlights more differences between the two optic types. Check it out to know more.
Lastly, though not entirely necessary as most, if not all, prism scopes come with their own mounts, you’ll want to take into consideration the different mounting options available. Different prism scopes use different mounts; they can vary in height and may be either uncomfortable or incompatible with other sight apparatuses like magnifiers.
Best Prism Scopes
It’s impossible to determine what the “best” prism scope is, since that answer is entirely subjective and usually based purely on personal preference. We can, however, provide some options to help you round out your knowledge of what some of the most popular options are.
Regardless of which model you choose, it’s important to check out manufacturer websites to get as much info as possible before pulling the trigger on a prism scope. Doing additional research and ensuring that the optic’s glass, casing, and internals are of high quality will go a long way in helping you in your search.
Primary Arms SLx MicroPrism™
You’ve likely seen our SLx MicroPrism™ series sights available on our store page. Their design and durability make them an incredible option to add to your rifle, and with the many reticle variations and magnification options, there’s a sight available for every purpose.
Our SLx MicroPrism™ optics are tough, compact, and affordable to maximize value. There’s a wide array of different reticle options available in this line of optics, each tailored for specific purposes, and in some cases, different calibers. For example, the Primary Arms SLx 3x MicroPrism™ Scope can come with the ACSS Raptor Reticle optimized for 5.56/.308 or 7.62×39/300 Blackout. Additionally, our SLx 5x MicroPrism™ can come with an illuminated ACSS Aurora MIL reticle, or the standard ACSS Aurora reticle. This makes the 5x more than versatile enough for long range competitive shooting and hunting.
Currently, Primary Arms Optics MicroPrism scopes can come in 1x, 3x, or 5x magnification, making them more than capable of filling any role necessary. We also have more traditional prism scopes with 1x, 2x, 2.5x, 3x, and 5x magnification, so there’s a choice for every range and budget. For added value, we carry a wide array of different accessories tailored to our prism scopes, so you can easily configure them for your rifle setup.
Vortex Spitfire Series
Coming from the venerated manufacturer, Vortex, the Spitfire prism scope is another great option to add to your rifle. Currently, they’re available in 1x, 3x, and 5x magnification, and made from a shockproof rugged construction. Like most prism scopes, the Spitfire is nitrogen gas purged to make it fog-proof as well as waterproof.
The 3x and 5x variants utilize their AR-BDC4 reticle, which is optimized for use with the 5.56 cartridge while the 1x spitfire only comes with their DRT (Dual Ring Tactical) reticle, which can be used with any caliber. The DRT reticle is more akin to a red dot sight with additional rings. It can be used to rapidly acquire targets, being like EOTech’s circle dot reticle. In contrast, the AR-BDC4 reticle provides more options for holds and is better overall for making shots at distance.
Trijicon ACOG (Advanced Combat Optical Gunsight)
Arguably the most iconic prism scope available, the Trijicon Advanced Combat Optical Gunsight, or ACOG, has been in use for decades. Just like the previously mentioned prism scope is available in various magnification levels. As of right now, they offer options in 1.5x, 2x, 3x, 3.5x, 4x, and 5.5x magnification. They do offer a 6x variant of the ACOG, but it’s designed specifically for use on machine guns, so its weight may be prohibitive for most uses.
The ACOG has a multitude of reticle options available, depending on which magnification option you choose. Some of the options include a Circle Dot, Crosshair, Triangle, Horseshoe Dot, and Chevron reticle, just to name a few.
For maximum reliability in adverse conditions, ACOGs are waterproof and shock resistant. Each optic is dry-nitrogen filled to eliminate fogging and boasts zero distortion in the glass. One of the key features of the ACOG is its dual illumination sight. The ACOG utilizes a fiber optic tube in conjunction with Tritium to maintain brightness when not in direct light.
Using a Magnifier with a Prism Scope
When it comes to using a magnifier on a prism scope, it’s possible to use one on a scope model with 1x magnification, but keep in mind that this doesn’t work on all 1x prism scopes. For instance, our SLx 1x MicroPrism™ was designed to be able to be used in conjunction with our magnifiers. On this model, the eye relief is much more forgiving than other 1x prism sights, making it one of the best prism scope models available for you to feasibly use a magnifier with.
If your prism scope has any magnification above 1x, it’s not likely that you’ll be able to effectively use a magnifier. Doing so distorts the reticle image, and often increases the parallax shift and makes your sight picture blurry. However, if you use the right optic, you’ll get plenty of benefits.
Essentially, it’s the same in practice as running a magnifier on a red dot sight. It will broaden the overall ability of the optic, being able to switch from 1x to a magnified setting quickly. Having the ability to quickly magnify your optic will give you better long-range target identification and enhance your engagement ability. Unmagnified, you don’t make any sacrifices on performance, meaning you’ll still have quick target acquisition and great eye relief.
There are some drawbacks to using a magnifier that you should take into consideration. Like we mentioned before, it can be tricky to properly set up a prism scope with a magnifier. Depending on the optic, you’ll either get really good results, or less-than-desirable ones. Like using a magnifier with a red dot, your eye relief will shorten, and your sight box will be considerably smaller. Fortunately, it’s easy to quickly change between the two sight options, making these drawbacks negligible with proper training.
Can you use a Prism Scope with a Red Dot?
One of the ideas that’s been making its rounds recently stems from a photo taken during the GWOT in 2003 that features an operator using a 4x ACOG behind an EOTech, essentially using the prism scope as a fixed magnifier. This has sparked many enthusiasts to consider doing this.
While it’s possible to use a prism scope in conjunction with a red dot, it isn’t really worth the trouble. Essentially, the idea is for the prism scope to work as a fixed magnifier. In fact, most magnifiers available are constructed the same way as prism scopes, just without reticle etching. While a good idea in theory, it often makes the sight picture crowded and blurry, while also adding a significant amount of weight to your rifle.
As finnicky as this setup is, and how costly it can become, we don’t recommend that you go this route. Instead, we recommend you use a high-quality magnifier to do the job. Also, there are some people who want to attach their prism scope to an FTS mount. Doing this compounds the problems mentioned above and also prevents you from having a repeatable zero when using the prism as an aiming device.
As prism scope technology has progressed, there isn’t really a need to run dual-optic setups like this. You can, however, use a mini reflex sight as a backup to your prism scope. By utilizing an offset mount, you could use a magnified prism sight for long range engagements, and an offset mounted red dot for close range. Doing this gives you the best of both worlds in terms of sight acquisition and accuracy.
Conclusion
The versatility of prism scopes is incredible. Their rugged reliability, dependability, and form factor make them more than effective alternatives to traditional style variable power optics. Though they’ve helped bridge the gap in variable power optics and red dot sights, it can be a big commitment to select a single magnification option.
By better understanding prism optics themselves, it becomes much easier to decide what magnification to use on your rifle. Considering what your purpose is for using a prism scope will go a long way in narrowing down your search. Continue researching sight options by visiting manufacturer websites and other articles like our guide on what prism scopes are.
If you’re reading this and debating on whether or not a prism scope or red dot sight will work best for you, read our 5 things to know when buying a red dot article. It goes over all of the key details and facets of the sight and will give you a better understanding of which optic is the right one for you.
In the ever-evolving landscape of rifle optics, prism scopes will continue to be a fantastic addition to add to your rifle. Regardless of whether your purpose is hunting, competition/duty, or recreational shooting, a prism scope is a great way to maximize your versatility.