Rock Island Armory RIA 5.0 9mm Hammer-Fired Semi-Auto Pistol

The all-new Rock Island Armory American-made RIA 5.0 is a dramatically different breed of 9mm. Brad Fitzpatrick gives us a full review.

June 21, 2023 By Brad Fitzpatrick

When I got the assignment to review a new 9mm semiauto pistol from Rock Island Armory, I was neither surprised nor particularly inspired. 9mms are the lifeblood of the pistol market, and dozens of new nines appear on the pages of this magazine every year. But with so many 9mms being virtual doppelgangers of pistols already in production from other manufacturers, testing and evaluation becomes fairly routine.

Occasionally, though, something turns up that is totally outside traditional lines, and that’s the RIA 5.0 from Rock Island Armory. If you assumed this pistol to be a striker-fired, polymer-frame gun you’d be dead wrong on both accounts. If you imagined it was very much like something you’d seen before, that’s not likely. The RIA 5.0 is a completely new and revolutionary semiauto. It was designed and built in Cedar City, Utah—the first Rock Island/Armscor pistol made stateside.

Rock Island Armory RIA 5.0 9mm Hammer-Fired Pistol Controls — Controls include a large, easy-to-operate slide stop and a mag release button. The two indexing dots—one on the slide, one on the frame—assist in disassembly. (Mark Fingar photo)

The first impression of the RIA 5.0 9mm semiauto is that of a pistol someone drew from memory. The proportions seem incorrect: The slide is too short when compared to the frame; controls seem to be missing; and the whole gun looks a bit too blocky. However, the engineering elements that give the RIA 5.0 these odd proportions serve important functions.

Let’s start with the barrel. When viewed from the front, the squared-off barrel narrows slightly toward the bottom, and it fits tightly into the cutout in the steel slide. The RIA 5.0 features internal slide rails that are similar in concept to the CZ 75. The design lowers bore axis and slide height, and the internal frame rails increase bearing surface between the slide and frame. That increased bearing surface can help stabilize the slide, but it only works if the machining and surface finish reduce friction—as is the case with this Rock Island. In fact, the RIA 5.0 is one of the smoothest-operating guns I’ve tried that doesn’t come from a custom pistolsmith.

The majority of modern pistols use recoil-operated tilt-locking barrels, a design perfected by John Moses Browning. In short, after the gun is fired the muzzle portion of the barrel tilts up and allows the barrel and slide to separate during operation. The RIA 5.0 eschews that design. Instead, the RIA 5.0 utilizes something called a Ram Valve System. It employs a block under the barrel that prevents the gun from operating until pressures are safe, at which point the recoil energy is used to cycle the action.

rock-island-armory-ria-50-hammer-fired-semi-auto-03 — The barrel appears to be square in cross-section, but it actually tapers slightly toward the bottom. Rail cuts increase bearing surface between the slide and frame. (Mark Fingar photo)

In many regards it’s closer to a blowback design than a traditional tilt-barrel recoil design—in that the barrel remains in a straight, fixed position. There’s a front locking block through which the guide rod and recoil spring pass, and this block interfaces with a cutout in the barrel to lock everything in place. It’s simple but ingenious.

The results of this design are direct rearward recoil force and less muzzle rise. And since the barrel remains in virtually the same place instead of unlocking and tilting, accuracy potential is very good. The square barrel adds weight to the front of the pistol, and the RIA 5.0 is noticeably nose-heavy, but that helps mitigate recoil. Aside from the rather unusual square design, the barrel doesn’t require the locking lugs found on other pistols.

Polymer grip inserts are pinned in place in the anodized aluminum frame, and the grip features nice wraparound texturing. The modular design makes the grips easy to remove and swap out, but the supplied grip is very good and is big enough to accommodate large hands. The rounded lower portion of the backstrap and beavertail promote a high hold on the pistol, as does the molded undercut in the trigger guard.

Guns with internal frame rails can be built with a very low bore axis. However, the RIA is an internal hammer-fired pistol. Traditionally, being a hammer-fired pistol would negate the gains of having internal rails because the pistol’s firing assembly would be taller than its striker-fired counterparts.

The RIA 5.0’s inventor Fred Craig, who is famous for creating the .22 TCM cartridge, found a way to reap the benefits of a low bore axis in his hammer-fired creation by minimizing the size of the firing assembly. The RIA 5.0’s assembly is seated deeply inside the aluminum frame, and this allows the bore to sit low in the hand.

Rock Island Armory RIA 5.0 9mm Hammer-Fired Pistol Ram Valve System — The Ram Valve System doesn’t use a tilt-barrel design but rather harnesses recoil energy in a linear fashion. This keeps the barrel in virtually the same position between shots. (Mark Fingar photo)

Combine the RIA 5.0’s low bore axis and revolutionary linear operating system, and it becomes clear this is a gun designed to mitigate recoil effectively. Recoil is directed in a straight line through the shooter’s arm, the pistol stays level, and the shooter can retain the sight picture, and follow-up shots can be delivered rapidly.

The RIA 5.0 trigger uses a transfer bar and is very light. It features a safety blade, and after a smooth, light take-up the break on my sample averaged four pounds, four ounces. RIA could have made this trigger even lighter, but 4.25 pounds is a good setting for factory pistols. In my opinion, the RIA 5.0 is one of the few 9mm pistols that comes with a competition-ready trigger right out of the box.

The RIA 5.0’s steel slide is finished in black Cerakote. It has angular serrations at the front and rear and comes with a fully adjustable LPA black rear sight and a red fiber-optic front sight. There’s also a run of 300 RIA 5.0 pistols with C-More reflex sights. The standard model I tested didn’t come with a slide that’s cut for optics, but there is a large five-slot rail on the pistol’s dust cover.

There are few controls. The large slide-lock lever doubles as a transverse takedown pin, and there’s a reversible mag release button. That’s it.

Field stripping the RIA 5.0 is relatively simple, but you’ll want to have some idea of what you’re getting into and how the system works before you start tearing everything apart. With the magazine removed and the gun unloaded, pull the slide rearward until the two indexing dots on the frame and slide align. Press the exposed portion of the slide stop on the right side of the pistol, remove the slide stop and then the slide.

The Ram Valve System, guide rod and recoil spring can then be removed, and the locking block located under the front portion of the barrel will drop free. From there, the barrel slides forward and out of the slide.

Rock Island Armory RIA 5.0 9mm Hammer-Fired Pistol Accuracy Results

Despite its name, the RIA 5.0’s square barrel measures just 4.91 inches in length for an overall length of 8.11 inches. The pistol’s weight was 40.4 ounces on my digital scale, less than an ounce above the listed weight.

At 1.33 inches across its widest point, the RIA 5.0 could conceivably be carried, although it features 1911-esque dimensions and mass. Height is listed at 5.17 inches, which is about a quarter-inch shorter than competing guns in this size category like Glock’s G17 9mm and Armscor’s own Rock Standard FS 9mm 1911 (5.47 and 5.51 inches tall, respectively).

The RIA 5.0’s metal is finished in black Cerakote and comes with two 17-round metal magazines.

As I mentioned, the RIA 5.0 is an unmistakably nose-heavy pistol, and that’s likely the first thing you’ll notice when you pick it up. In a world overrun with micro-compact 9mm carry pistols, this is more of a race gun, designed to be shot accurately and quickly in competition or defensive settings.

While we typically do not associate added weight with speed, the linear recoil, minimal muzzle rise, good trigger, quality sights and weight-forward balance make this gun a very fast shooter. That weight in the front also keeps this pistol stabilized as you transition from one target to another and keeps the front of the gun settled for improved accuracy. Once you get in rhythm, shooting the RIA 5.0 is like being in tune with a sports car: The machine becomes an extension of the operator.

While you will notice the reduced recoil when shooting two-handed, if you really want to see the difference, shoot it one-handed side by side with a similar size 9mm. I knew the RIA 5.0 was manageable while shooting it, but it wasn’t until I shot it one-handed alongside a Glock G19 that I realized how substantially the design reduces recoil. With the RIA 5.0 I could shoot single-handed and stay on target whereas I’d have to re-center the Glock each time.

The trigger guard is oversize, and you can easily shoot this gun with gloved fingers. The magazine release is easy to access, and the empty mags drop free every time you press the button.

Rock Island Armory RIA 5.0 9mm Hammer-Fired Pistol Internal Hammer — The pistol is fired via an internal hammer. The blacked-out rear sight is from LPA and is adjustable for windage and elevation. (Mark Fingar photo)

The worst thing to happen to 9mm pistols was the advent and popularity of the “minimized” (read: worthless) slide stop. The RIA 5.0’s slide stop is designed for shooters who need to put shots downrange in a hurry and is therefore large enough to operate easily and consistently. There’s lots of room on the aluminum frame for an aggressive thumbs-forward grip.

Accuracy was excellent. A few groups dropped below 1.5 inches, but this gun consistently shot two inches or better with multiple loads. That’s better than I’ve come to expect from 4.5- to 5-inch 9mms, which typically average between 2.5 and 3 inches accuracy at 25 yards.

With a quality reflex optic in place this gun has the potential to be extremely accurate. What’s most interesting to me is how consistently this pistol performed with different loads, as you can see in the accompanying chart. That’s something I rarely encounter in factory pistols.

Incidentally, I happened to grab Federal’s Syntech PCC 130-grain pistol caliber carbine 9mm loads by accident, and by the time I realized my mistake while loading magazines at the range it was too late to switch them. To my surprise, this load proved to be the most accurate of the test and produced a 1.38-inch five-shot group.

Reliability was good throughout, the only issue being that the RIA 5.0’s slide didn’t lock every time the last round was fired.

Shooting the RIA 5.0 offhand is where it really shines, and there’s no doubt competition shooters will appreciate this gun’s design. But this is also a very good gun for new shooters as well because it’s smooth shooting and offers basic, easy-to-use controls.

A friend’s wife just bought her first 9mm pistol, a subcompact carry gun weighing 22 ounces. It has tiny controls and a heavy recoil spring. There’s nothing wrong with the gun, but it’s not a great choice for a novice shooter like the RIA 5.0 is. If I were teaching instructional shooting courses I’d have a few of these on hand for rookies.

The RIA 5.0 is a refreshingly different pistol, and while it may not be everyone’s cup of tea, this is a great gun with a unique and advanced design. Will it lead to a whole new era in semiauto handgun design? Time will tell, but the RIA 5.0 has the goods to win over pistol shooters.