More and more people are discovering what an advantage it is to have an optic on their pistol…
Yes, there are some people out there who are still resisting it, but the truth is, that an optic on your pistol helps you shoot faster and more accurately…
It’s actually been fairly common to put optics on larger handguns for a few years, but now, a lot of people are mounting optics on their concealed carry guns…
And since these guns are usually slim, single stack handguns, your typical optics like the Trijicon RMR and the Holosun 507c are simply too big…
So more and more manufacturers are starting to produce tiny optics designed for these single stack concealed carry guns, and right now, two of the most talked-about options are…
- The Holosun 507k (Check Price On Amazon – Over 1,172 Reviews)
- The Sig Romeo Zero (Check Price On Amazon – Over 360 Reviews)
So in this Holosun 507k Vs Romeo Zero comparison, we’re going to see how these two little optics stack up to each other in the following 6 categories…
- Durability And Toughness
- Lens Clarity And Reticle
- Size Comparison
- Battery Life And Brightness Settings
- Extra Accessories Included With The Optic
- Price Comparison
In the end, I’ll tell you if I prefer the 507k or the Romeo Zero, and you should have all the information you need to determine which optic will work best for you…
Let’s start by taking a closer look at the durability and toughness of these two optics…
Durability And Toughness…
Holosun 507k
The Holosun 507k is a very durable little optic. To start off with, it has a sight housing that’s constructed from 7075 T6 aluminum, which is a very rugged material…
In addition to that, it has an anodized finish which will help protect the sight from the elements…
On top of that, the windage and elevation turrets are designed in a smart way. Both of them are recessed into the site housing…
And that prevents them from ever getting bumped accidentally or even snapped off, which is something that can happen on red dot sights…
The Holosun 507k is also waterproof. It’s rated to be waterproof in up to 1 meter of water for 30 minutes…
I think it can handle a lot more water than that, but regardless, it can easily handle rainy, snowy, or wet conditions without giving you any problems at all…
Last, the 507k was designed from the start to be a pistol optic, and because of that, it’s also shockproof…
It can easily handle the abuse of being mounted on a handgun slide, which is definitely an important feature for any optic intended for use on a concealed carry handgun…
All in all, the durability and toughness that you get with the 507k is extremely impressive.
Romeo Zero
The Sig Romeo Zero has a sight housing that’s constructed from polymer…
Now Sig calls it a “weapons grade ultralight polymer” housing, and for what it is, I think it’s fairly durable, but it’s certainly not as tough as aluminum…
In addition to that, the windage and elevation turrets on the Romeo Zero are recessed into the sight housing just like with the 507K…
Again, I think that’s an important design feature because it will prevent your adjustments from getting bumped or snapped off accidentally…
And it also keeps the sides of the optic smooth, so they won’t get caught on clothing when you’re concealed carrying the sight on your gun…
Now the lens on the Romeo Zero is also made out of a polymer which is supposed to be more durable than a traditional glass lens, and I’ll take Sig at their word on that…
On top of that, the Romeo Zero is rated to be waterproof in up to 1 meter of water for 30 minutes just like the 507k…
And it’s also shockproof because it was designed from the start to be mounted on the slide of a handgun.
Durability And Toughness Conclusions…
In this category, there are some pretty significant differences between these two sights…
First of all, they’re both rated to be waterproof in up to 1 meter of water for 30 minutes, and they’re both shockproof…
In addition to that, they both have windage and elevation adjustments that are recessed into the sight housing…
However when it comes to the material of the sight housing, the advantage has to go to the Holosun 507k…
No matter how you slice it, the 7075 T6 aluminum on the 507K is a much more rugged material than the polymer used on the Romeo Zero…
So in this category, the clear winner is going to be in the Holosun 507k.
Winner: Holosun 507k
Lens Clarity And Reticle…
Holosun 507k
The Holosun 507k has a very clear lens. You don’t really get much of a blue tint when looking through the sight the way you do with some other red dots out there (like the Trijicon RMR)…
And overall, you can see clearly through the optic and get a very clean sight picture…
Now as for the reticle, with the 507k you get a feature that Holosun calls the Multiple Reticle System or MRS…
Basically, this means that you get 3 different reticle options within your sight (the Holosun 407k has a fixed reticle)…
The 3 reticle options are…
- A 2 MOA dot surrounded by a 32 MOA ring (the Holosun Circle Dot)
- A 2 MOA Dot
- A 32 MOA ring without the 2 MOA dot in the center
All 3 reticles have strengths and weaknesses. So let’s go through and discuss each one in a little more detail…
The first option is the 2 MOA (minute of angle) dot surrounded by the 32 MOA ring which is also called the Circle Dot reticle…
This is an awesome reticle. It’s pretty much my favorite reticle on this style of optic and there are a couple of reasons why…
First of all, the large 32 MOA ring is very quick and easy for your eye to pick up, which allows you to shoot faster…
But at the same time, you still have the little 2 MOA dot in the center for aiming at small targets or targets that are off in the distance…
It helps you shoot faster without sacrificing any of the precision you would need for high accuracy shooting, and because of that, I really like it…
The second reticle option is a 2 MOA dot. This is also a great reticle in my opinion especially if you think the circle dot reticle is too cluttered, which is the case with some people…
The 2 MOA dot is still large enough that it allows your eye to pick it up fairly quickly, but you still have the small dot for shots that require precision…
The last option is the 32 MOA ring with no dot in the center. I’m actually not a huge fan of this reticle, but that being said, let me explain why some shooters like to run it…
The 32 MOA ring is large, so you can shoot very quickly with this reticle, especially at large targets that are at close distances…
And not having the dot in the center of the ring allows you to see your entire target. The obvious downside, however, is that you have no fine aiming point for precise shots…
So if you’re just worried about shooting large targets up close, it’s a reticle that can work really well, but it will probably not offer you the precision to shoot with a high degree of accuracy at small targets or targets that are in the distance…
In the end, all 3 reticles have benefits and drawbacks, but one of the best things about the 507k is that you can try all of them out and then settle on the one that works best for you.
Romeo Zero
The Sig Romeo Zero also has a very clear lens. Again, you don’t notice too much of the blue tint that you get with some red dot sights…
And overall, you can see clearly through the optic and get a clean sight picture…
Now when it comes to the reticle on the Romeo Zero, you have two options. You can either get the version with a fixed 3 MOA dot or the version with a fixed 6 MOA dot…
Out of these two options, I prefer the 3 MOA dot because I feel it’s big enough for your eye to pick up the dot fairly quickly, but the small dot size gives you more precision…
But even though I tend to prefer a smaller MOA dot size, there are tons of really great shooters out there who like to run a 6 MOA dot…
So in the end, it really is a matter of personal preference, but like I said, I prefer the smaller dot because it offers you more precision…
And remember you can always crank up the brightness level to make the dot bigger if you need too.
Lens Clarity And Reticle Conclusions…
So in this category we have some big differences between these two sights. First of all, they both have a very clear lens that allows you to get a clean sight picture…
But after that, they are completely different. The Holosun 507k features the Multiple Reticle System which gives you 3 reticle options in the same sight…
Like I mentioned earlier, I prefer the Circle Dot Reticle because it helps you shoot faster without sacrificing any accuracy…
But the other 2 reticle options certainly have their place as well. On the other hand, the Romeo Zero will have either a fixed 3 MOA dot reticle or a fixed 6 MOA dot reticle depending on the verison that you get…
I think the Multiple Reticle System is superior to the fixed options that you get with the Romeo Zero. So in this section, I’m going to give the win to the Holosun 507k.
Winner: Holosun 507k
Size Comparison…
Holosun 507k
Like I mentioned earlier, both of these optics are designed to be mounted on small, single stack handguns that are intended to be used for concealed carry…
So it’s needless to say that they’re both going to be fairly compact. In fact, the Holosun 507k is a smaller version of the Holosun 507c…
Now the height of Holosun 507k measures in at 0.95 inches. The width measures in at 0.98 inches, and the length measures in at 1.60 inches…
In addition to that, the 507k has a weight that comes in just 1 ounce…
Romeo Zero
Like I mentioned already, the Romeo Zero is also a very compact optic…
It has a height that measures in at 0.93 inches. It’s width measures in at 0.93 inches, and its length measures in at 1.6 inches…
In addition to that, the Romeo Zero has a weight that comes in at only 0.4 ounces…
Size Comparison Conclusions…
Both of these sights are extremely compact, and their dimensions are very similar…
That being said, the biggest difference in this section is in terms of their respective weight…
The Holosun 507K weighs in at 1 ounce, whereas the Romeo zero is only 0.4 ounces…
I always prefer my optics to be as lightweight as possible. So in this section, I’m going to give the slight win to the Romeo Zero…
Winner: Romeo Zero
Battery Life And Brightness Settings…
Holosun 507k
The Holosun 507k uses 1 CR1632 battery which is able to power the sight for 50,000 hours when the optic is on brightness setting 6…
That’s awesome battery life, which is something I’m always looking for on a red dot sight…
The reason why long battery life is so important is because you don’t want your optic’s battery dying on you at the wrong time…
I’ve had red dot sights die on me at the range before, and even though that can be really annoying, it’s not the end of the world because you can just swap out your battery when you get home…
But what you really want to avoid is your optic’s battery dying on you in an emergency self defense situation…
With 50,000 hours worth of battery, it’s not likely that that will happen with the 507k, especially if you follow the standard advice of swapping out your battery at least once a year (some people say to do it on your birthday)…
Now when it comes to swapping out the battery on your sight, Holosun makes it really quick and easy with the 507k…
You see, there are some sights out there in which the battery is changed from the bottom of the optic…
That’s actually a huge problem because it means you’ll have to take the sight off of your gun every time you want to change out the battery…
…and then you’ll have to re-mount the optic and re-zero it after putting it back on.
That’s all a huge pain in the neck for a simple battery change, and it’s something you get to avoid with the 507k because it has a sideloading battery tray…
So you can keep the optic on your gun, and simply swap out the battery in a couple of minutes, which is awesome…
Another really cool feature that you get with the 507k is Holosun’s Shake Awake technology…
This basically means that your sight will automatically turn off after a period of non-use and automatically turn on as soon as the sight senses motion…
So it will help save your battery life, which is already very long, and at the same time your optic will be ready to go as soon as you touch your gun…
Now with the 507k you get 10 daylight brightness settings and 2 night vision settings. The daylight brightness settings are very powerful on the high end and get very bright…
So you won’t have any issues with your reticle washing out on you, even if it’s a really sunny day outside…
In addition to that, I like that Holosun includes the 2 NV settings with the 507k at no additional cost to you…
…because if you do end up running your gun at night with NV equipment, your optic will be ready to go.
The last feature I’ll discuss in this section is something that Holosun calls the Lock Mode. It’s found on the Holosun 507k X2 version of the sight…
And basically, it allows you to lock in the brightness setting of your choice. This is a cool feature because even if the brightness buttons on your sight get accidentally bumped…
The optic will stay locked in at whatever brightness setting you selected. So if you ever do need to draw your gun in a life or death situation…
…your optic will be at the perfect brightness level for the conditions you’re in (not way too bright or way too low and barely visible).
All in all, the Holosun 507k is a sight that is packed with features that are useful to you as the shooter (even features you won’t find on much more expensive sights).
Romeo Zero
The Sig Romeo Zero also uses 1 CR1632 battery which is able to power the sight for around 20,000 hours…
That’s not quite as long as the 507k’s battery life. However, once you get past a year’s worth of battery life…
…I think you have a sufficient amount of time because you should be swapping out the battery once a year anyway.
Now when it comes time to swap out the battery on the Romeo Zero, unfortunately, the battery is stored in the bottom of the optic…
That means you’ll have to take the optic off of the gun to change the battery…
…and then you’ll have to re-mount the optic and then take your gun to the range and re-zero your optic.
Like I said earlier, that’s a huge hassle, and it really makes changing out the battery a lot longer process than it should be…
Now on a more positive note, the Romeo Zero features the MOTAC system which stands for “Motion Activated Illumination”, and it’s basically the same thing as the Holosun Shake Awake feature…
So your optic will automatically turn off after a period of non use which will save you battery life, and it will automatically turn on as soon as you touch your gun…
Now with the Romeo Zero you get a total of 8 daylight brightness settings…
Like the settings on the 507k, they get very bright on the high end, and you won’t have any problems with your reticle washing out on a sunny day…
There are no night vision settings on the Romeo Zero, but I don’t think that’s too much of a problem because most people don’t have NV equipment and would never end up using them anyway.
Battery Life And Brightness Settings Conclusions…
Once again, we have a category in which these two sights have a lot of significant differences…
To start off with, they both have pretty long battery life and an auto on/auto off feature (the Shake Awake and the MOTAC system)…
But that being said, the battery life on the Holosun 507k is significantly longer than the battery life on the Romeo Zero, and when it comes time to change the battery…
With the 507k you can simply change it without removing the sight from your gun…
Whereas with the Romeo Zero, you will have to remove the optic to change the battery, and then you’ll have to re-mount it and re-zero it, which is a huge hassle…
Aside from that, the 507k includes 2 NV settings just in case you end up wanting to run your sight in the dark…
And it has the Lock Mode, which you can use to lock in the perfect brightness level…
So in the end, I think this is another category in which the Holosun 507k comes out as the clear winner…
Winner: Holosun 507k
Extra Accessories Included With The Optic…
Holosun 507k
The Holosun 507k comes with one CR1632 battery. I think it’s nice that Holosun includes a battery with the optic…
…because it means that you won’t have to run off to the store just to start using your sight (once you receive it).
It’s ready to go right out of the box, and I think that’s the way it should be with all optics…
In addition to that, you also get a lens cloth which is pretty much an accessory that comes with every optic you purchase…
The best included feature on the 507k is the rear sight that is built into the sight housing…
I think this is an awesome addition, and there are a couple of reasons why…
First of all, these tiny optics are designed to go on very small and slim guns that are intended for concealed carry…
And because of that, there’s not always a lot of space on the slide of the gun…
Some guns that come from the factory ready for an optic will actually not even have a rear sight when you mount the red dot on the slide…
I’m a firm believer that battery powered optics should always be backed up by iron sights…
So the fact that Holosun includes a rear sight on the actual optic itself means that all you need is a front sight to back up the 507k…
Now the footprint on the 507K is a proprietary footprint…
That’s not a problem for me because these tiny pistol optics are kind of a new invention, and there really is no standard footprint yet…
So even though the 507k has a proprietary footprint, it can still be easily mounted with an adapter plate…
…or you can have a competent gunsmith cut out your slide specifically for the optic, which is what I actually recommend.
Romeo Zero
Just like the 507k, the Romeo Zero comes with a battery, so it will be ready to go as soon as you receive your optic…
In addition to that, it also has a rear sight integrated into the sight housing which again, I think it’s a very good thing for this style of optic…
The downside is that the rear sight (like the rest of the sight housing) is made out of polymer, and that can be a problem if the optic is being put under hard use…
Now the footprint on the Romeo Zero is actually the same footprint as the Shield RMSC…
I think that’s a good thing because the Shield RMSC footprint is probably the most common footprint out there for these tiny reflex sights…
But as I said before, there really is no standard at this time, so I don’t think it’s a huge advantage over the proprietary footprint featured on the 507k…
That being said, it should be fairly easy to mount the Romeo Zero either directly onto a slide or with the use of an adapter plate.
Extra Accessories Conclusions…
In this category, these two sights are actually pretty similar…
They both come with a battery, and they both feature a rear sight built-in to the sight housing which, again, I think is a very important feature…
In addition to that, 507k has a proprietary mounting footprint, whereas the Romeo Zero uses the Shield RMSC footprint…
I don’t think either footprint gives you a significant advantage over the other when it comes to mounting the optic. So again, I think it’s pretty even here…
With all that being said, I think that these two optics are so similar in this category that I’m going to call it a draw.
Winner: Draw
Price Comparison…
Unfortunately I won’t be able to give you exact numbers in this section of the comparison because the prices of these sights are known to change as the market fluctuates…
But that being said, in general, you’ll usually be able to find the Romeo Zero for around 100 to 110 bucks less expensive than the Holosun 507k…
That’s actually a pretty substantial chunk of change, and it could be a factor if you’re trying to keep the price of your optic as low as possible…
So if you are on a tight budget, keep in mind that the Romeo Zero is going to be the less expensive option for you.
Winner: Romeo Zero
Holosun 507K Vs Romeo Zero – Final Thoughts…
So to sum it all up, in the Durability And Toughness category, both the Holosun 507k and the Sig Romeo Zero are waterproof and shockproof…
However, the sight housing on the 507k is constructed for 7075 T6 aluminum…
…whereas the sight housing on the Romeo Zero is made from polymer, which is much less rugged. So the 507k was the clear winner in this section.
In the Lens Clarity And Reticle category, both sights have a very clear lens and allow you to get a clean sight picture…
However, the 507k features the Multiple Reticle System which gives you 3 options in the same optic (including my favorite the Circle Dot Reticle)…
And the Romeo Zero only has a fixed 3 MOA or fixed 6 MOA reticle. So I gave the win the 507k in this section…
In the Size Comparison, both optics are extremely compact and have very similar dimensions…
…but because the Romeo Zero is just a little bit more lightweight than the 507k, it came away as the slight winner here.
In the Battery Life And Brightness Settings category, both sights have an auto on/ auto off feature which is cool…
However, the 507k has a lot longer battery life, the side loading battery tray, NV settings, and the Lock Mode feature. So once again, it came out as the winner…
In the Extra Accessories category, both sights come with a battery and a built-in rear sight. So I called it a draw in this section…
And last in the Price Comparison, the Romeo Zero is usually around 100 to 110 dollars less expensive than the Holosun 507k…
So which of these sights do I prefer? I prefer the Holosun 507k…
I prefer the Holosun 507k for a few reasons. First of all, the 507k is a much more durable optic than the Romeo Zero…
It has a high quality aluminum sight housing, as opposed to the polymer housing found on the Romeo Zero, and it’s simply a much tougher red dot sight…
That’s an extremely important feature if you’re mounting the optic on a gun that could be used for self defense, which is the case for a concealed carry gun…
In addition to that, I prefer the Multiple Reticle System on the 507k over the fixed dot options on the Romeo Zero…
Like I said earlier, I really like the Circle Dot Reticle because it helps you shoot faster without sacrificing accuracy…
…but with the 507k, you’ll be able to play around with all 3 reticles before you settle in on which one is right for you…
The battery life on the 507k is also much longer than the battery life in the Romeo Zero. So its very unlikely that your sight’s battery will end up dying on you…
And the battery change is quick and easy on the 507k because it has the side loading battery tray…
Last, I also really like the Lock Mode feature that you get on the 507k because you can set your brightness to the perfect level and then lock it in…
So even if the buttons on your sight get bumped around a little bit, the optic will still be ready to go if you even need to use it…
Now if you just intend to use the sight as a range optic (so durability isn’t a huge factor), and you want to save a few bucks, then feel free to go with the Romeo Zero…
Either way, I hope I was able to show you the major similarities and differences between these two tiny little reflex sights.