Here are the 3 best red dots for Sig P320 (M18) that are compatible right out of the box. These are proven optics on many other pistol platforms, and they will do great on the P320.
Let's check it out...
3 Best Red Dot For Sig M18
Leupold DeltaPoint Pro - Best Overall
The Leupold DeltaPoint Pro 6 MOA is a top red dot for Sig M18 with a bigger dot that works very well with all full size or compact.
The DeltaPoint Pro has been around on the market for a very long time, and it's large size window helps the shooter acquire the dot much faster than other smaller optics.
For the money, this optic is much more durable, and it's a great competition optic to use on other guns you may have..
In addition, the top-loading battery access makes battery swap easy without sight removal.
See detailed DPP reviews and pics here
$60 off $600 (use code: MC4) – Complete the build you have been saving up for
Trijicon RMR - Best For Duty Use
(M17, M18, X Five slides require RMR hole drilling)
The Trijicon RMR is another best red dot for Sig P320. The type 2 model is re-engineered to handle repeated pistol slide cycling and holds the battery tighter to ensure 100% connectivity.
The user however still has to access the battery from the bottom, which means re-zeroing the optic is required after a battery swap. If you want the same durability but an optic that lets you change battery without sight removal, please check out the Holosun 507C below.
Or check out the Trijicon SRO here
Holosun HS507C ACSS Vulcan - Best Dot Acquisition Performance
(M17, M18 slides require RMR hole drilling)
The Holosun 507C ACSS Vulcan is an upgrade to the original model, and this time it features the ACSS Vulcan reticle specifically designed to help the shooter find the dot faster and track the dot better if lost in the field of view.
The 250 MOA size outter ring acts like an directional indicator for shooters to recenter the reticle.
The user can also turn off the outter ring and just use the ACSS triangle reticle for precise aiming. Out of all the red dot options, Holosun is doing something very innovative to help shooters that struggle with finding the dot.
Above all, the 507C holds the same 7075 T6 aluminum durability as the original model and the RMR. Highly recommended checking it out
See more pics and reviews here
Sig Sauer P320 Optics Compatibility
The new P320 Pro cut and P320 RXP are conceal carry ready with slide optic cut for Sig ROMEO 1 Pro and Deltapoint Pro.
Check out CHPWS plate they have a large selection of optic plates specifically cut for each different variant of P320 Slides.
If your slide ONLY has the ROMEO 1 Pro cut, then the RMR, SRO and Holosun 507C can't be mounted unless you send the slide to a shop to get it drilled.
If you slide features the RMR and ROMEO 1 Pro/DPP holes, then all you need is a RMR plate.
Building Your Own P320 Slide
If you want to build your own P320, Yes! you can buy a custom optic ready slide.
Check out the best aftermarket P320 optic ready slides here