What the heck does "For the RMR(SRO/407C/507C🤯) footprint" mean?

Man.... where do I get started, this was supposed to be simple, These loonies. They ought to throw a net over the whole bunch of ‘em!

No that's not right, we are talking about the often misrepresented 'RMR Footprint', named after the Trijicon RMR, the pistol red dot you see in movies.

So what is the actual deal with this so-called "footprint" and the long list of asterisks additions oft included that have been made to it over the years. Well if you are here for an extensive deep dive, too bad, we are going to skim most of the stuff you don't care about and get to the meat.

So in 2009 Trijicon dropped the hottest optic since hotcakes, it was more or less the successor to the Docter optic and many other "Micro" red dots. If that is simple Docter would later be butchered into Doctor and Micro means about 20 different things talking to our customers (but definitely doesn't have any real meaning if I am being honest here).

Anyway back in the day it was amazing, and it was almost so good Trijicon waited 14 years to update it, they were a little late to party though. The main thing that separates the 'RMR Footprint' from basically every other non-RMR-footprint derivative footprint is that it has screw holes that are 18mm apart. Basically, every other footprint that matters has screw holes that are 14mm apart. If you want to quickly tell whether you have an RMR footprint optic or some other heathen heretic-based footprint you can do so with a penny or a dime..

14 mm non-RMR based footprint on the left vs 18mm RMR derivative footprint on the right.


For purposes of using our optic, if the screw holes on your slide can only be roughly halfway covered with a penny(a dime also works), any of our optics made for the RMR footprint will fit. That includes the Wolf0, Wolf2/-G, Wolf PRO, Wolf X PRO, CT2, Bull PRO, BULL X PRO, and BEAR with the use of RMR Footprint adapter plate.

That is quite a lot of optics that fit, that is because the majority of full-size optics are made for the RMR footprint or an RMR footprint derivative. Explaining derivatives is usually pretty straightforward, in this case, if your optic has the RMR Footprint it can fit any of the following footprints, RMR, SRO. 407C, 507C, 508T, or basically any that use 18mm screw holes. Screws needed vary by which footprint is being used and who made it. If your optic is a 407C, 507C, 508T or strictly uses their footprints, you cannot use the RMR footprint. So the best footprint to have is the RMR Footprint as it will work with derivatives, but derivatives will not work with strict RMR Footprints...


With THAT said most people will refer to any of the above footprints that use 18mm as RMR footprints... and in fact, manufacturers have gone steps ahead of optics makers to do all kinds of modifications to the footprint.

Slide with the front recoil posts moved to the screw holes to work with a larger number of optics


Some manufacturers have gone as far as to completely get rid of the recoil posts altogether

This is not ideal and should be avoided if possible. While this may not have problems functioning you are more likely to have a red dot that shifts without recoil posts.

If you have a footprint without recoil posts you should take extra precautions, like marking screws and using 242 medium-strength thread-locker equivalent. You will likely be fine but for an unlucky few if you have issues, changing the optic many times over won't help if there are other problems adding to a cut without recoil posts.

Out of all the optic cuts, the RMR footprint is the easiest to work with if your optic is actually using an RMR Footprint. Derivatives being misidentified as "RMR footprint" don't matter for practical application, and derivatives will often be misidentified. But what optic cut should you get if you have a choice between the RMR footprint and the 407C/507C footprint?

The thought process may occur to you since the RMR Footprint optics can be used with the 407C/507C footprint but vice versa is not possible, to get the 407C/507C footprint. Taken from the perspective of an average everyday user, if you are not 100% sure which optic will be on your gun for the next few months and are extremely tight on budget that may be the option for you. For those of us out there who understand the 407C/507C aren't really anything special anymore, measure twice and cut once. You can always remove more from your slide, you can't as easily put it back. The recoil posts of the RMR Footprint are beefy, and there for a reason, if you're using an RMR footprint optic, use an RMR footprint,


Full test for determining if you have an RMR Footprint cut


We are Cyelee Optics are absolutely committed to making the best optics possible, and that means as little proprietary nonsense as possible. When we make optics we make them to work with as many people's firearms as we can! Which is why we opt to use standards made for the RMR footprint as opposed to trying to fix what isn't broken.

If you want to support us as we bring optics priced at pre-discounted wholesale dealer prices, as we make it as simple as owning a penny to get started please give one of our optics a try today! Other brands may say they have a lifetime warranty but charge you twice over for the courtesy, many will not cover optics accidentally damaged but instead ask you to purchase again at a "discount". We at Cyelee have a written promise to replace all optics with verified defects with new ones, not used ones like many other companies. We have written guidelines that solidify our promise to replace accidentally broken optics for the foreseeable future and 99% of our returns and replacements are processed in 3 days or less!



   ⚔️ SWORD

"I write articles on cyeleeoptics.com"

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