Swampfox Optics Sentinel II: Best New Micro Red Dot?

A relative newcomer to the optics world is Swampfox Optics. Swampfox Optics has made (and is making) quite a splash in the affordable optics market, offering several practical and tactical optics from higher powered rifle scopes to lower powered/variable powered optics for tactical applications, red dots and prism sights. All their optics have received acceptable reviews and are generally well received across the board. Users like their image clarity and ruggedness, build quality and features, making them an easy competitor for their peers. With Swampfox expanding, updating, and modernizing previous models, I was able to snatch up one of their new Sentinel II red dots for testing, as I am a fan (and somewhat a specification snob) of micro red dot optics. I find them to be quite a game changer on carry/defensive handguns and sub-machineguns/pistol caliber carbines (PCCs).

Straight out of the gate, the specifications on the Sentinel II are quite impressive, from construction to battery life to advertised specifications alone, it is a definite contender for multiple roles. Powered by a CR2032 battery, Swampfox advertises “up to” 50,000 hours of battery life on a single battery. This is branching into Aimpoint ACET (Advanced Circuit Efficiency Technology) battery life area and is theoretically far superior to the majority of its peers. Even so, if carried for personal protection, it’s still always best to change batteries yearly like all other trusted accessories and optics. 

Construction is robust yet lightweight, with an impressive 20mm lens diameter, offering a generous field of view. The Sentinel II is feature and specification rich. The micro red dot sight (RDS) is constructed from 7075-T6 aircraft aluminum alloy yet weighs in at less than an ounce (.99-oz). This is great for those looking for a lightweight option for sub-compact or mid-sized carry handguns. The Sentinel II features an IPX7 waterproof rating, which equates to 30 minutes, submerged in 1m (3 feet 3.37 inches). It features a singular dot, measuring at 3 MOA and an open emitter. The dimensions are 1.84(L) x 1.07(W) x 1.07(H) inches and features 10 different brightness settings that should fit most applications encountered by most users. Adjustments are solid and consistent, offering 1 MOA adjustment per click, with a generous field of adjustment range of 40 MOA +/-, equating to a total of 80 MOA, both windage and elevation. The Sentinel II offers nicely coated lenses that are anti-fog, scratch resistant and hydrophobic. Overall, quite acceptable specifications, nice construction, and quite clear glass. 

The Swampfox Sentinel II is quite robust in construction and nicely designed, with a lot of 7075-T6 aluminum surrounding the lens. I was quite glad to see this, as Swampfox seems to have designed this optic with rough handling in mind, with optimal protection from drops and severe blows that may damage other optics. For added protection on top of this already quite sturdy optic, they also offer a SUS304 blackened stainless protective shroud known as the Swampfox Ironsides Shield. This clever play on words is a historic callback to the U.S.S. Constitution, a Revolutionary War era U..S Naval heavy frigate with the nickname “Old Ironsides.” With its 304 Stainless construction, it does live up to the name given. Swampfox opted for a “between” dot size, which I prefer. I find for handguns, a 2 MOA dot is too small, while a 4 MOA dot is too big. Call it Déjà vu from a well-known children’s fairy tale, but to me, the 3 MOA dot is just right. The emitter produces a crisp, clear dot, which is quite easy and effortless to use. Coupled with nice, large and quite clear glass, the Sentinel II is a breeze to use on most handguns. I like the “shake awake” feature as well, as this conserves battery life and turns the optic on when needed. 

The Swampfox Optics Sentinel II has a unique design feature, which incorporates a “backup” iron rear sight into the frontal portion of the optic. This design feature is actually ingenious, as many smaller handguns forfeit rear iron sights with the removal of their optics plate. This is simply the nature of the beast, as many small handguns simply lack the real estate to have both options. While far from precise, they will get the user in the ballpark and will produce solid center mass hits at practical distances. I found this a neat and unique addition, but I opted to remove the backup irons for most applications, as I prefer a longer sight radius (as we all know, handguns don’t have a great sight radius to begin with) and it somewhat negates having that large, 20mm lens. Admittedly, I used this mostly on a Shadow Systems MR920, Lonewolf Dawn 365 and FNH 502 for testing, which all have dedicated irons either built into the optics plate, or dedicated iron sights on the slide.

While considered a “Micro RDS” and marketed as such, the Sentinel does have a larger profile than its Trijicon RMR counterpart. While minimal, this could be a deal breaker for people with small builds or those who wish to save every miniscule bit of space possible. This optic size would be perfect for any handgun ranging from a GLOCK 19 to a GLOCK 43x. I personally feel that the Sentinel feels a bit “large” for a P365, but it works, and one could definitely get used to it (especially considering the lens size advantage). Because of this, I would consider the Sentinel II more along the lines of a “hybrid” sized RDS, somewhat bridging the gap between the smallest of micro RDSs and something along the size of an Aimpoint ACRO or Steiner MPS. It offers a larger lens diameter and field of view than its peers, all while not feeling as “constricted” as its direct competition. The sight picture feels much more “natural” and works great on handguns of all sizes. The ironsides shield, while adding protection overall, may be considered redundant to some users and adding bulk and weight to others. While coupling the ironsides shield with the Sentinel II has a combined weight of roughly that of the Sentinel’s peers, to some, it may seem like an unnecessary waste of weight and space. I personally would opt for the shield, as many of us believe Murphy is in fact, out to get us (Murphy’s Law) many will opt out, as “ounces equate to pounds” in carry guns.

The parallax is likely my biggest concern on the Sentinel II. This Micro RDS is “parallax free” at 33 yards. While I haven’t noticed a massive shift while using this optic, this is again a Micro RDS, made and designed for carry handguns. With handguns, most practical engagements happen from point blank to 10 yards, most of which are on average, 7 yards. Most practical people practice from point blank to 25 to 30 yards, all of which fall under that 33-yard minimum. Again, I personally haven’t noticed a massive difference or shift. The concern is still there, and one that has me somewhat perplexed, considering the purpose in which it is designed. Even on an SMG or PCC, the parallax is 1/3 of their practical range. Because of this, I would likely rule the Sentinel II out as a Micro RDS for Shotguns or Short Barreled Shotguns (SBS), but would begin considering it as a lightweight optic for a lightweight, handy Short Barreled Rifle. While the inclusion of the removable iron sight was a definite plus in the design and execution department, I can see a handful of potential drawbacks that some users may experience. Users that opt for varying height iron sights, especially those made for suppressor use, may render the rear irons inoperable, making the backup irons practically useless. For factory height sights (both aftermarket and factory), the backups will work well enough to pull through an emergency situation. I can see many removing them or simply leaving them off (as I have) to take full advantage of the large sight window. 

So, Swampfox’s Sentinel II, how is it? Especially in comparison to other Micro RDS’s on the market? Overall, I have to give it a thumbs up. It is a well-constructed, well designed, well executed optic that gives the user a lot for their money. The Sentinel II has nice 1 MOA adjustments, a great sight window with a large field of view, clear glass and a bright, crisp 3 MOA red dot. It feels rugged, the lens is well protected, and it doesn't sacrifice weight for construction strength.  Weighing in at a low .99-ounce, the designers really did their homework on the construction versus weight ratio. Couple that with the SUS304 shield. It makes for quite a rugged combination for defensive carry. I again have to come back to their parallax free window, 33 yards is a lot of space for an optic geared for carry handguns, defensive handguns, potential shotgun use, or SMG/PCC use. Overall, though, it is a nice optic for an attractive price point. With an MSRP of $269 and $39 for the Ironsides stainless steel shield, the Sentinel II gives Vortex, Primary Arms, Burris, and others clear competition. 

Swampfox Optics Sentinel II Specs

• Type: Micro red-dot sight
• Magnification: 1X
• Objective: 20mm
• Weight: .99 oz.
• Battery Life: 50,000 hrs. (middle setting)
• Battery Type: 2032
• Dot Size: 3 MOA (Red or Green), 10 brightness settings 
• MSRP: $269
• Manufacturer: Swampfox Optics