Aimpoint Mounting Solutions

Aimpoint’s ACRO red-dot optic (specifically the revamped and improved P-2 model) has become popular and not just with shooters who want to put it on a handgun. If you look at the ACRO P-2’s specs, it actually outperforms Aimpoint’s Duty RDS — meant to go on AR-15s and the like — in battery life, shock resistance, and waterproofing while being lighter. People are mounting the ACRO P-2 to AR-15 SBRs and pistols, and non-handgun use is getting so popular that Aimpoint is now offering flip-up lens covers for the sight.

However, the ACRO’s unique mounting interface provides some challenges. Instead of screws coming up from below, securing it to a mount, the ACRO has a shallow sideways clamp and indexing rib built into its base, and these don’t fit on Picatinny rails. If you want to put the ACRO on a tall mount meant for a flattop AR, this isn’t an issue, but if you want to mount it low on a gun, that proprietary mounting system gets in its own way. Luckily, the ACRO has been around for a while and is popular enough that you have some interesting options if you want to mount the ACRO to various non-AR-15 firearms. Note that the Steiner MPS uses the same mounting system as the ACRO.

From Aimpoint themselves or other sources, you can buy a low mount meant to clamp atop a Picatinny rail. This “rail upon a rail” setup will add 22mm of height, which works if you’re looking for a little bit of elevation. 

However, if you’ve got iron sights on your firearm, that elevation might be enough to prevent using them through the window of your optic. I try to always plan for the worst-case scenario, so if I had an ACRO on a gun meant for serious work and couldn’t see the sights through the optic, I’d want it in a quick-detach mount. There are a number of them on the market. (Aimpoint makes one.) Perhaps the nicest one is the quick-detach (QD) mount from ADM, and it is made in several heights. The low mount is about 22mm tall and puts the centerline of the red dot .92 inch above the top of the rail.

There are a number of firearms with receiver rails where you might not want a full-height, AR-style mount. The CZ Scorpion EVO comes immediately to mind, but there are also AKs and various traditional rifles with rails directly atop the receiver/barrel, such as the Marlin lever-actions with scout rails. On those guns, even 22mm of elevation might be more than you want.

Announced at the 2024 SHOT Show, Reptilia has an ultra-low rail mount for the ACRO. Instead of putting the clamping screw in the middle of the mount as is traditional, the folks at Reptilia moved it forward, just in front of the sight body. The sight is clamped to a thin sled of aluminum just a few millimeters above the rail. The beefy mounting screw to attach the mount to the rail comes up just to the bottom of the optic’s window. This mount adds an inch of length, but it is the lowest option for mounting an ACRO to a rail.

This isn’t the first mount Reptilia has made for the ACRO. The Aimpoint ACRO/Steiner MPS saddle mount for Beretta shotguns is so good that Beretta was using one in all of its marketing materials for the new A300 Ultima Patrol.

Reptilia’s saddle mount for the ACRO works on both the Beretta 1301 Tactical and the A300 Ultima Patrol. Even though those two shotguns use completely different bolts and operating systems, the receivers have the same external dimensions. Both shotguns come with 3-inch rail sections attached to the top of the receiver, and the screw pattern is the same between both shotguns.

Simply unscrew the receiver rail on the shotgun and, using the same screws, attach the Reptilia saddle mount to the receiver. The optic then clamps to the mount. It puts the optic as low as possible on the gun, less than a ¼-inch off the receiver. It’s so low that you can easily use your sights through the optic.

HK MP5-pattern pistols have been popular for the last 10 years. The design is robust and reliable, and most guns are now sold with a short rail at the top of the receiver. However, these rails come up nearly to the line of the iron sights. If you want your dot above the iron sights for an uncluttered field of view, a low 22mm mount or something taller might be what you want, but that will pull your cheek off the stock or brace. If you want your dot down low, staying true to the ergonomics of the gun, there are now dedicated MP5 mounts that replace the generic rail with an ACRO mounting surface. These put the ACRO low enough that you can see your iron sights through the optic. Some offer a direct co-witness sight arrangement.

Infitech, a Swedish company I stumbled across, makes excellent co-witness MP5 mounts for the ACRO that use both the front and rear receiver mounts. They look great, but at $177 they’re not cheap.

Both HK Parts and Titan Tactical Designs make small, low co-witness mounts for the ACRO that utilize just the rear claw mounts on the MP5 receiver. The HKP product ($99) clamps in from the sides, whereas the TTD ($65) clamps with upward pressure on the receiver footings, which is more common. Smaller mounts like these seem nicely suited for the shorter MP5K pistols and SBRs.

I tried both the HKP and TTD out on an HK SP5, which I have SBR’d, and they both seem to work great. You can see your sights through the bottom of the optic in these low mounts, and this keeps your face on the stock. However, as a result, it makes the field of view more cluttered; the dot is halfway between the top of the front sight and the protective ring above it. I honestly don’t know if I like these low mounts better than one that puts the dot above the front sight ring … but I like that I now have the option to choose. 

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