In a recent thread, I mentioned that a few days ago at the LGS, there were three of us there, and one guy had a 48 MOS with a 507K, my wife had a 365XL with a 507K, and I had a direct milled 43X with a RMSc. Obviously slimline pistols and red dots are a great combination, as the dot makes up for less sight radius. Since the hardware is becoming more reliable and available, I thought it would be good to start a thread on some considerations around selecting, installing and using dots on slimline pistols.
I think the most common optics suitable for slimline pistols are the RMSc, the 407K/507K, the Romeo Zero, the RMRcc and the Swamp Fox Sentinel.
I have had a number of Shield RMS and RMSc optics over the past few years. For the last year plus, I have been frequently carrying a 43X with a 8 moa RMSc (polymer lens). After scratching up an early Shield, I have been very particular about how I clean the lens. I try to use compressed air to remove dust and debris, and sparingly use a Leupold Len pen. So far, this has kept my lens free of scratches. The optic has held zero perfectly for me. I really like the combination of the large dot and the Shield’s auto intensity. The RMSc design integrates nicely with standard height iron sights. Battery life is not as long as an RMR, and with no side loading battery drawer, the optic has to be removed to change the battery. So far, zero has held for me when removing and reinstalling the optic. A great attribute of the Shield design, is the optical clarity of the dot in low and adverse sun angles — I only see one dot and there is no splatter. The RMSc footprint is nearly the industry standard on factory cut slimline pistols.
I have not used a 407K, although I have had multiple 507K optics. I like the controls and side loading battery. I wish the dot was larger. At one point I thought I didn’t like the auto feature, until I realized it had no auto function, just manual and manual with a lock out. Sure helps to read the manual! I find the 507K is terrible in a low sun angle setting with the single dot selected — it is either washes out completely or has enough splatter, you can’t decipher which is the main dot. A work around is using the circle dot reticle, as that works perfectly in adverse sun conditions. While I find it harder to call my shots with the Holosun circle dot, I feel like the circle dot reticle may be the best 507K choice for EDC, where shot calling is not as important as having a visible reticle across a wide range of lighting conditions. One caution is that while the 507K footprint is close to the RMSc, it is slightly different and won’t drop on without modification.I do believe that an optic direct milled for a 507K will work with a RMSc.
I bought a RMRcc as soon as they came out, but after having it sit unused for months, I traded it on a SRO. I really wish Trijicon used the RMSc footprint, because it’s unique footprint makes it less desirable to me. I will be curious as to what pistols people are using the CC on and how they are working out.
I also got a Swamp Fox, but as of yet haven’t mounted it.
Early reports on the Romeo Zero were disheartening, but I haven’t heard much lately.
Feel free to pile on with your experiences with these optics, particulars of mounting these optics on slimline pistols, plate options and other observations.