The Ultimate .22LR Competition Build: Zermatt RimX Review

With rimfire precision matches growing in popularity, I wanted a setup that could replicate centerfire PRS-style shooting while offering the training benefits of rimfire affordability. My goal was to build the Ultimate .22LR Competition rifle, and after about a year in the making, I think I finally did it! Creating the ultimate .22LR bolt-action competition rifle started with a lot of research and ended up with a no-budget build. After target shooting and competing with this rifle at a PRS22-style match, I can confidently say this build performs as good as it looks. Here’s a breakdown of each core component and how it contributed to building the ultimate .22LR competition platform.

Zermatt RimX Action

At the heart of this rifle is the Zermatt Arms RimX action. Unlike many rimfire actions trying to mimic centerfire geometry, the RimX is a true-to-scale Remington 700 footprint designed specifically for competition and training. This means you can use it in standard R700 inlets and pair it with any compatible trigger or chassis. This was a huge bonus for modularity and those piecing together their ultimate rifle builds.

I opted for the 30 MOA top rail version (0, 20, 30, & 40 available) to gain more elevation travel. This is especially useful when shooting out to 400+ yards with a 22LR. Zermatt offers six bolt knob options, but I chose their competition variant. While it worked loose from the factory, a touch of blue Loctite will keep it locked in place. Great size and form factor, and it ran well for me.

The bolt was consistently smooth throughout my first match, even in windy conditions. My only minor gripe was the 90-degree bolt throw. I would love to see a 60-degree throw option, which would have felt even faster for rapid follow-up shots. Still, the bolt handle offered a great purchase, and I had zero extraction or feeding issues all day with good ammo. Being a 22LR, it surprised me how good the action was. It felt better than many of my centerfire rifles, and with a tuned mag fed like a dream.

Zermatt RimX Magazine

The action ships with a 10-round aluminum magazine, which, while pricey at $125 per mag, is incredibly robust and feeds reliably. These can be tuned for how high they sit in the action. From the factory, I had to adjust mine slightly to feed consistently. However, once set, the RimX magazine fed without a hiccup. While it is very well made, not having other affordable magazines to choose from when they are $125 a pop is about the only downside I have found to this build so far.  But I went into this trying to build the ultimate rifle and spare no expense, and these magazines are top-notch. I have never handled a better-made magazine.

Proof Research Pre-Fit RimX Barrel

Pairing the RimX with a Proof Research pre-fit barrel made the setup quite simple. The 20-inch steel barrel I used came with a 1/16 twist, 1/2-28 threaded muzzle, and a competition contour that balances weight and stiffness. Proof is known for its carbon fiber barrels, but their steel variants shoot lights out and have proven to be just as consistent. At the range, this barrel impressed me with how well it handled a variety of ammunition. It especially liked Norma TAC-22 and select Eley offerings, shooting constant sub-MOA groups. 

Even after strings of fire, the barrel remained cool to the touch. I ran ten rounds in under ten seconds, and it still wasn’t even warm. While 22LR doesn’t generate a lot of heat, having a barrel that can dissipate it appropriately to get consistent shot after shot on target is a big deal for a competition rifle.

This barrel also features 1/2 X 28″ muzzle threads which will work for those trying to run tuners, brakes, or suppressors. The end of the barrel is just over 1″ in diameter, so small 22 cans almost look flush, which is also kind of neat. The rifle seemed to shoot just as well suppressed as unsuppressed.

TriggerTech Diamond Trigger

I’ve used many triggers over the years, and the TriggerTech Diamond remains one of the best. This single-stage trigger is completely free of creep and has a crisp, glass-like break. The Diamond variant is adjustable from 4 to 32 ounces, which means you can tune it down for benchrest precision or up slightly for positional shooting under time pressure.

For this build, I tuned the trigger right around the 10-12 ounce mark. Just enough to give me control under NRL-style stress without being too twitchy. Every time I pulled the trigger, I knew exactly when it would break, giving me added confidence on small targets in shifting wind.

MDT ACC Premier Gen2 Chassis

The MDT ACC Premier Gen2 chassis brought everything together. This chassis is already one of the most respected options in the PRS world, and its updated design borrows several enhancements from the higher-end ACC Elite line. I appreciated the taller integrated barricade stop, more rigid forend, and a full-length ARCA rail that made adjusting my bipod or tripod position seamless across various props.

One of the biggest highlights was its ability to perfectly balance the rifle using MDT’s external M-LOK forend weights. Tuning the center of gravity just forward of the magwell made shots off a barricade, tree branch, or tire incredibly stable. I also ran the MDT CKYE-POD Gen2 Double Pull bipod and found it gave me the steadiest positions of any bipod I’ve ever used. Between the chassis adjustability, vertical grip, and cheek riser tuning, I custom-fitted this chassis to my shooting style.

Installation was also easy. Two screws to torque down, and you’re off to the range. This chassis was designed with competition in mind and delivered on every front. For these reasons and many others, it proved to me why this chassis is a top choice for many in the centerfire and rimfire PRS leagues.

Vortex Razor HD Gen III 6-36×56

While some might say a 6-36x scope is overkill for a .22LR, I completely disagree. When engaging ¼-inch targets at 50+ yards or steel at 300+ yards, having that magnification and clarity gives a real edge. The Vortex Razor Gen III 6-36 is one of the most proven optics in long-range competition. Its glass is incredibly crisp, the turrets track true, and the EBR-7D reticle is perfect for fast holdover adjustments.

A standout feature for me was the micro-adjust zero setting that allows for zeroing between clicks. This is a rare feature that lets you get absolutely dialed when zeroing. The scope also uses the L-Tec+ Zero System, making the turret adjustments straightforward and bombproof. Throughout the match, I used this scope to spot my misses and send quick follow-ups with accurate corrections. It’s not cheap, but it delivers.

I am also a fan of the Vortex EBR-7D reticle. I have owned this scope for a while and used it across various rifles in different situations. From centerfire, PRS matches shooting out to 1400 yards, to a PRS22 match shooting from 50-300 yards, holdovers, and wind calls were quick and intuitive. The .03 MIL center dot also gives a super fine aiming point without being distracting. This was perfect for my 22-match when I was shooting at targets the same diameter as the bullet I was sending down range.

Match Performance and Real-World Use

I tested this rifle at a rimfire PRS match where wind gusts reached up to 15 mph. The rifle ran flawlessly. I was holding 13.5 mils of elevation for some 300-yard shots, which is equivalent to a 1350-yard shot with a 6.5 Creedmoor. This is why I say precision 22 competitions are a fantastic way to practice wind calls and elevation holds affordably.

The action stayed smooth all day, and even during 10-round stages, the Proof barrel never warmed up. Just to test it, I ran 50 rounds back-to-back, and the accuracy held strong throughout. The MDT chassis added excellent stability, and the crisp break of the TriggerTech Diamond gave me confidence in every shot. I engaged everything from tiny ¼-inch plates at 54 yards to gongs just past 300 yards and this rifle hit them all. The full build weighs about 18.2 pounds, which helps it stay completely flat while firing. On calm stages, I could easily watch my bullet trace without losing it to recoil.

Throughout this review, I was able to put hundreds of rounds through this RimX rifle build. Most of the ammunition used was provided by Ammuntiontogo.com. They are the official ammo sponsor for this rifle review and offer a wide selection of competitively priced ammunition. They have quick shipping, an easy-to-use online website, and competitive prices. Go check them out! 

Accuracy Results

Aiming to see how well my ultimate 22LR rifle could shoot, I set up with a wide variety of ammo. I then shot 5-round groups from about 50 yards. All bullet speed information was captured by a Garmin Xero C1 Pro chronograph. Norma Tac-22 and Eley Match were the standouts, but all premium match ammo performed respectably. Eley Semi-auto benchrest achieved the best SD and ES of all the ammo I tried, but SK and Lapua also performed very consistently. Shown below is a table and pictures of the groups I received: 

READ MORE HERE: Build Your Own Precision Rifle

Final Thoughts

This build was designed to push the limits of what a .22LR is capable of. Specifically in a competition setting, it exceeded almost every expectation. Whether it was the flawless feeding from the RimX action, the custom-fit feel of the MDT chassis, or the laser-like clarity of the Razor scope, each component served its purpose exceptionally well. Those combined with the TriggerTech Diamond trigger and Proof Research barrel made for one heck, and dare I say, the ultimate competition rifle.

If you’re serious about rimfire competition or want a .22LR that mimics your centerfire PRS rifle in both form and function, this setup delivers. This rifle is staying in my rotation, and I’m already looking forward to more matches with it soon. 

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