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Window sizes on Popular Pistol Red Dots

rfgCA

CGN Member
Calguns Verified
Messages
198
Sharing my excel file for some Pistol Red Dots, this one sorted by Aperture or Objective Area (Window Size), with some other info.

Sorted from largest window to smallest (in mm). Might be of help to someone deciding what to get:

optics2.png
 
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I appreciate the footprint section!

I have a G19.3 that is milled for a 507C but I want to jump on the enclosed emitter game (without running a separated
adaptor plate). Its been difficult to figure out what red dot has what footprint, especially when some manufacturers don't explicitly state it (*cough* Holosun *cough*).

Based on your chart, I may look into the 509T.
 
I appreciate the footprint section!

I have a G19.3 that is milled for a 507C but I want to jump on the enclosed emitter game (without running a separated
adaptor plate). Its been difficult to figure out what red dot has what footprint, especially when some manufacturers don't explicitly state it (*cough* Holosun *cough*).

Based on your chart, I may look into the 509T.
Yeah, it's annoying because an adapter changes co-witness height.

Also according to Holosun, the 509t uses an "rmr to 509t" adapter, so you're getting a plate on that rmr cut with the 509t either way.
 
Nice chart.
SRO is round, seems misleading to just do Area = Width * Height

Thanks. The SRO aperture area listed is relatively accurate.

Although the SRO is aspherical due to a small flat area at the bottom, it is almost oblong. To get the area of an oblong, the formula is the same as getting the area of a rectangle. Length x Height.

The straight line at the bottom of the window is very near the tip of the oblong, and it might only account for a few sqmm.

I appreciate the footprint section!

I have a G19.3 that is milled for a 507C but I want to jump on the enclosed emitter game (without running a separated
adaptor plate). Its been difficult to figure out what red dot has what footprint, especially when some manufacturers don't explicitly state it (*cough* Holosun *cough*).

Based on your chart, I may look into the 509T.

Thanks. Although I don't own a 509T, I've read that the 509T ships with an RMR Adapter. So if you have an RMR slide, you won't need to spend extra for an adaptor. Best of luck, post pics!
 
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Yeah, it's annoying because an adapter changes co-witness height.

Also according to Holosun, the 509t uses an "rmr to 509t" adapter, so you're getting a plate on that rmr cut with the 509t either way.

Luckily for me, I'm not too worried about the co-witness height as I'm running suppressor-height sights.

I prefer a direct mount without a plate, but I understand that 509T mounts to a RMR adaptor plate regardless. Its just tough when all of these newer enclosed optics tend to run a RMSc or other footprint....
 
The SRO is oblong. To get the area of an oblong, the formula is the same as getting the area of a rectangle. Length x Height.
That can't be right. Sro is very close to a circle and there's no way a rectangle of the same width and height doesn't have a larger surface area, what with corners.

Figured it would be easy enough to cut a 22.5 x 25 piece and compare it to my sro.

Missed your edit. 😉
 

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That can't be right. Sro is very close to a circle and there's no way a rectangle of the same width and height doesn't have a larger surface area, what with corners.

Figured it would be easy enough to cut a 22.5 x 25 piece and compare it to my sro.

I've edited my post to explain it a little more.

Although the SRO is aspherical due to a small flat area at the bottom, it is almost oblong. To get the area of an oblong, the formula is the same as getting the area of a rectangle. Length x Height.

The straight line at the bottom of the window is very near the tip of the oblong, and it might only account for a few sqmm - good enough for gov't work.
 
How about CMORE RTS3?
I have to write in to CMore to get their actual window size as it's not easy to calculate the aspherical window size (Circular, with long flat bottom). But definitely will be up there among the largest, if not "the" largest. (I estimate mid 600sqmm)
 
I was disappointed to learn sig Romeo X enclosed pro and enclosed compact have the same window size. Only thing different is the footprint. Feels like you should get some extra window space for the extra money you spend on the pro cut.
 
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