Low Power Variables vs Low Power Fixed Magnification

With my recent purchase of the newest generation of ACOG, and my ignoring the similarly priced low-power variable market, I thought it would be worth posting some of my thoughts on the two competing segments.

Browsing optics discussions on various gun boards would have you think that the age of the low power fixed magnification optic are gone. As one SME in the shooting world put it, “The ACOG was the perfect optic for pre 2004 conflict.” Even in my own article about different types of optics, I opined that low power fixed magnification (which I dubbed Class II optics) represented the skill set of the last generation of riflemen, before our focus turned to more close quartered combat.

Low power variable (LPV) optics have dominated the market in recent years. What started as a new concept useful for competitive shooters slowly worked its way into military units with the leeway to purchase whatever they wanted. Usage by these military units caused the civilian market to take notice. This started cycle whereby many companies entered the market and began innovating and driving prices down through competition.

The downside of the LPV has always been a combination of cost, weight, and durability. The added mechanisms required to change magnification meant introducing complexity and weak points. Combat-grade optics designed to survive harsh conditions necessitated extensive engineering, which increased cost. Up until very recently, you were unlikely to find a combat-worthy LPV for less than $2K. Competition in the market has brought that price closer to $1K, though, which directly competes with the ACOG segment.

With that in mind, why would anyone choose to go with a low power fixed magnification optic when it is possible to get a scope of comparable durability and optical quality for about the same amount of money?

Understanding Intangibles


For the sake of this discussion, I’m ignoring the market segment below $800. For now, I am purely talking about comparing optics like the ACOG and SpecterOS 4x to LPV scopes like the Vortex Razor and Nightforce 1-4x. Below $800, there are a lot of great LPV options from SWFA, Trijicon (the TR-24 has come down in price quite a bit), Leupold, and others. In that price bracket, there isn’t really much a difference between the fixed magnification and variable magnification scopes.

Once we cross into the realm of “enthusiast,” “prosumer,” or “professional” optics, things get more interesting.

We can list out all the specs on the various optics in these categories, examining weights, fields of view, illumination, reticles, parallax adjustment (or lack thereof), and other tangible items. The truth is that those things simply don’t matter as much in this bracket. In this segment it has much more to do with personal preference.

In the category of low power fixed magnification, optics tend to be lighter, brighter, more compact, and simpler in use. Most of the ACOG line, even the tiny TA-33 that weighs a scant 7 oz, have objective lenses wider than the average LPV (24 mm). That makes a difference in low light conditions, especially when it comes to target identification. Small sizes reduce snag hazards and overall bulk.

LPV scopes tend to be slightly more versatile for the roles they can be used in, and they often have more refined reticles, but come at the expense of increased weight and size. In general, I find the illumination to be weaker and more short lived due to smaller batteries. But that is with a sample size of three. I know there are some LPV options out there that are exceptionally bright, especially if they are fiber optic powered. LPV scopes might be friendlier to those with poor eyes, as things like parallax and ocular lens focus can be adjusted.

These are not absolutes, as there are some overlapping features depending on models in question, but this is a pretty good guideline to understand.


So who should choose what?

Having spent a lot of time with both LPV and fixed magnification, I can’t really see myself doing without either. Were I to be stuck with one rifle and scope for every task for the rest of my days, I would probably tend towards the variable market. But, since I’m not, I like having the option of taking a lighter and more compact scope with wide field of vision for some tasks. I like the simplicity of shouldering the rifle and firing, without worrying about fiddling with magnification settings or turrets that might have been bumped off of my zero.

In general, I would say the difference between users is this:

  • If you want magnification, but tend to stick to the 1x end of things (either via RDS or leaving a LPV at 1x), then stick to a LPV. I would avoid an RDS with magnifier arrangement.
  • If you tend to want magnification all the time, or have an LPV you leave on the high setting most of the time, and prefer the simplicity of shoulder-and-fire function while keeping a more compact package, consider a fixed magnification scope. You can always pair it with a mini RDS if you want to have that multi-role capability with minimal additional weight.
  • If you want magnification most of the time, precision is a priority, and you intend on fiddling with windage and elevation a lot, go with an LPV designed to do it. These will tend to have better reticles (MRAD/MOA) and matched turrets.
  • If you don’t know where you fall on this continuum, then it doesn’t really matter what you pick. In this case, I would consider getting a more inexpensive LPV and see how you tend to use it. As I said before, the sub $800 bracket has a lot of great options to start with and allow you to explore your preferences.

When I started this journey a few years ago, I was sure that I knew exactly what I wanted. I did my homework on internet, and I purchased quality optics. Ironically, one of those scopes doesn’t get used anymore and the other has been relegated to more of a backup role. The more experience I gain, the more I prefer the simplicity of grab-and-go without knobs and such to fiddle with. For that reason, I’ve been sitting strongly in the camp of fixed magnification scopes.