Red Dots for Small Format Pistols (43X & P365 size)

[Tensaw]

With the advent of the 43X/48 and P365 series, we are seeing various red dot sights mounted on the smaller width pistols. I am seeing everything from RMRs to other red dots specifically sized for these smaller width slides being mounted. Thing is, when you factor in Optics Ready slides; the various mounting/adapter plates; and the various red dot mounting footprints - the array of combinations is staggering, and getting more complicated daily. I thought perhaps we could have a thread dedicated to cataloging the various dots and mounting solutions for these smaller pistols; along with the pros and cons of each solution.

[evi1joe]

GUNS and SLIDES -->

P365: a lot of places use their own designs of milling for the same red dot (for example, the Shield RMSc).
Maple Leaf mills the slide with 4 lugs and the screw holes; other places only do two lugs up front, and I think the P365XL has only two very shallow lugs up front. Maple Leaf also has an adapter plate that mounts an RMR on to their RMSc cut, but the optic is pretty high for a tiny gun (see below). Even the Shield RMSc doesn't quite sit low enough for the OEM sights to be visible (maybe a hair if at all). I know there is a slightly taller SIG sight that works, but can't remember the name.

P365XL: You have to buy your own M3x12mm screws to mount an RMSc on this gun; however, I'm sure the RomeoZero will come with screws that fit. The new Holosun 507K/407K optics will fit on this gun, but won't directly fit on the HELLCAT or the Walther PPS since the holosuns only have two lug holes, up front, and they are more shallow than the RMSc and the RomeoZero.

G43X Grey Ghost Precision milled slide (RMSc): VERY TIGHT tolerances--sliding the optic in is like working with a revolver side plate; the angle has to be near perfect. It's so low that normal sights will easily be viewable over the optic but not obtrusive (unless you already have tall sights). Ameriglo I-dots were perfect.

HELLCAT: works with the Shield RMSc and the SIG RomeoZero, but will need to be reprofiled to work with the upcoming Holosun K-models.
Walther PPS optics cut model: same as the HELLCAT.

** G43X / G48 / 43 RMR milling options (taken from another site and edited):

1) The Primary Machine mount is the same one used for 1911s. It is pretty low, and I hear they have a fast turnaround, but all those sharp edges do not make for a clean looking setup. The leading corners of the plate are sharp, and also the bottom edge all along the sides of the plate. The other mounts have a taper, or chamfer that makes the plate blend better with the slide and have an overall cleaner look where the current design just looks like a shelf sitting on the slide with no blending. Plus the serrations on the top edge seem out of place and don't blend with the Glock. NOTE: according to users, none of the sharp edges ever contact skin or are noticeable when wearing it.

2) The Suarez plate looks done well, about as low as Primary Machine, but the plate doesn't quite match the width/footprint of the RMR so the RMR itself has a tiny bit of insignificant overhang edge to it. There aren't any recoil lugs on the top of the adapter plate which is probably due to the mount plate front screws being in the way. These were the first option to market, so there are a lot of them in use.

3) The Maple Leaf plate-adapter thing fits the RMR well, but it's pretty high. The RMR adapter plate does appear to have recoil lugs for the RMR which is nice.

4) The Mac Defense mount is the lowest (and most costly). To do this they put the rear sight in front of the optic. The plate blends well with the slide and sight. The plate appears to match the overall width and footprint of the RMR the best with no, or very little RMR overhang. I didn't see a pic of the plate, so I don't know if it has recoil lugs (mine will be here in a week, so I'll update this). The milling they do on regular width slides to mount an RMR directly do have lugs, so you would think the narrow slide adapter plate would as well...but Suarez puts lugs on his regular slides, and his plate lacks them.

**
NOTE: For any mount without lugs, I'd risk stripping a screw when replacing a battery. I'd use vibra-tite vc3 (water soluble, which might help if you soak it) or or MAYBE 243 loctite, then snug them to like 14lbs, and let it cure for 24 hours or more. I know the CHPWS people say not to use loctite with their mount (for MOS guns). Instead, they say to put the screws in to 13lbs (?) and then just put nail polish along the top of the screws...and people seem to think they're very rugged.

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One issue I've noticed is it's hard to find iron sights that work great for the 43X/48 when running a milled RMR. Suarez co-witness are too high, but Suarez low-witness are too short. Ameriglo 429s evidently don't fit the smaller slide. I like for sights to be pretty low and out of the way. I want to just see the top 1/2 to 3/5ths of the rear notch when it's lined up with the front sight. I really think we need a rear sight that's like .365-.385" high depending on how low you get it milled. Dawson could make them, but I don't want giant rectangle rear sights--I want a triangle shape to not block my lens.

My measurements with a crappy digital caliper:
Tall Suarez = .420” front -- .410"
Ameriglo 429 = .305" rear front -- .315
Short Suarez = rear -- .315” ... front -- .305"

[GJM]

This is my EDC 43X, with a RMSc direct milled by Primary Machine.

[Eric_L]

[QUOTE=GJM;990053]This is my EDC 43X, with a RMSc direct milled by Primary Machine.



You are still using the 8 MOA dot? And liking it?

[HeavyDuty]

This is my EDC 43X, with a RMSc direct milled by Primary Machine.

Can you say which iron sights those are, and how the cowitness is?

[GJM]

[QUOTE=Eric_L;990074]

This is my EDC 43X, with a RMSc direct milled by Primary Machine.

You are still using the 8 MOA dot? And liking it?

Yes and yes!

Can you say which iron sights those are, and how the cowitness is?

OEM Agent sights.

[Super77]

Is the rear sight notch built into the RMS-C usable buy itself or is it more to provide sightline for the rear sight?

[GJM]

Is the rear sight notch built into the RMS-C usable buy itself or is it more to provide sightline for the rear sight?

The integral RMSc rear sight is obscured by my OEM Bold rear sight, so I am not sure. A main advantage of the RMS a is being able to use regular height iron sights as BUIS, so unless there is no rear dovetail, not sure why you would use the integral rear sight.