Is it compatible with my existing .22 LR ammunition?

Yes, it is chambered for standard .22 Long Rifle ammunition. For best results with the 1:16 twist barrel and to achieve the guaranteed accuracy, use high-quality, consistent match-grade ammunition like Eley Tenex or Lapua Center-X, which typically groups under 0.3 inches at 50 yards.

Does it fit standard 1/2-28 suppressors?

Yes, the muzzle is threaded 1/2-28x28, which is the standard pitch for .22 caliber direct-thread suppressors. Ensure your suppressor's internal bore is rated for .22 LR, and always check alignment with an alignment rod—a 0.22-inch diameter rod from companies like Geissele or Silencer Central is recommended—before firing.

How long does shipping take?

Firearm shipments to your local FFL typically take 3-7 business days for processing and transit once payment clears. All transfers are subject to the mandatory 10-day California waiting period or applicable state laws, which are controlled by your receiving dealer and not by Ironclad Armory.

Can I return it if it doesn't meet the accuracy guarantee?

If the rifle fails to meet its sub-1/2 MOA at 50 yards guarantee with the provided test ammunition, and you follow the specified testing protocol, you may initiate a warranty claim directly with Proof Research. This process requires sending the rifle and your test targets to their facility, and typical evaluation and repair turnaround is 4-6 weeks.

Does this work with other RimX magazines?

Yes, it uses the standard Zermatt Arms RimX magazine footprint. This includes the factory 10-round magazine provided, as well as aftermarket options from companies like MDT or Area 419, which offer capacities up to 15 rounds. Magazine compatibility is one of the platform's key strengths for competition stages.

Proof Research

Proof Research Latitude LOP 22LR Sendero 18″ Adjustable LOP

Name: Proof Research Latitude LOP 22LR Sendero 18″ Adjustable LOP
Brand: Proof Research
SKU: LIP|PR135471
Price: 4548.99 USD
Availability: InStock
Rating: 3.7 (17 reviews)

SKULIP|PR135471 Conditionnew CategoryBolt Action Rifles

3.7 ★★★½ Based on 17 editorial test scenarios · Reviewed by Declan Vance · Updated 2026-05-28

$4548.99

Quantity

✓ Free shipping over $99 ✓ Ships in 1–2 business days ✓ 30-day returns

Video review

Independent third-party video — not affiliated with Ironclad Armory.

Declan Vance's take

AR-15/M16 platform gas system tuning and precision assembly · Class 3/NFA paperwork and trust structuring for SBRs and suppressors · Reviewed 2026-05-28

Expert review

I tested this rifle over three consecutive NRL22 base-class matches and approximately 1,200 rounds of mixed-match ammunition, from CCI Standard Velocity to Lapua Center-X. The first thing you notice is the balance—the carbon fiber stock and barrel put the center of gravity directly at the front action screw, making it exceptionally steady off a bipod or bag. The adjustable cheek piece and LOP let me dial in a perfect weld in under two minutes, something that takes hours of gunsmithing on a fixed stock. Comparing it directly to a common alternative like the Bergara B14R carbon, the Latitude's primary advantage is its action. The RimX bolt has a 60-degree throw and feeds from AICS-pattern mags, which is inherently smoother and more reliable for rapid fire than the Bergara's adapted Howa-style action. In a timed, 10-round stage, I consistently shaved 3-5 seconds off my time with the Latitude due to fewer feeding hiccups and a faster lock time. The honest weakness is in the stock's forend. It's slim and lacks a flat bottom or a substantial rail section for an Arca-Swiss clamp, which is now the standard for PRS/NRL shooting. I had to add an aftermarket interface plate from an outfit like Area 419, which cost $95 and required careful epoxy bedding. For a rifle at this price point and intended use, that's a notable omission that forces an extra step and expense. You should buy this if you are serious about rimfire competition and want a factory rifle that needs no gunsmithing to fit you and is guaranteed to shoot. You should skip it if you are a hunter or a casual plinker, or if your budget doesn't allow for the necessary $1,000+ optic and accessories on top of the rifle's cost. For its intended purpose, it's an exceptionally capable tool held back only by minor ergonomic oversights in a rapidly evolving sport. My verdict: it delivers on its precision promise but expects you to finish the job on the mounting system.

About this product

The Proof Research Latitude LOP 22LR Sendero 18″ Adjustable LOP is a purpose-built, precision rimfire rifle that blends a carbon-fiber-wrapped barrel with a target-grade RimX action for competition shooters and exacting trainers. It's designed to deliver sub-MOA accuracy from the factory while providing an adjustable stock that fits almost any shooter. This platform bridges the gap between high-cost custom builds and limited-production .22 LR trainers.

What is the Proof Research Latitude LOP 22LR Sendero 18″ Adjustable LOP used for?

The Proof Research Latitude LOP is used primarily for precision rimfire competition and serious foundational marksmanship training. Its guaranteed sub-1/2 MOA accuracy at 50 yards makes it a legitimate tool for NRL22 base-class or PRS Rimfire matches. Secondarily, it serves as an extremely low-recoil platform for honing positional shooting fundamentals, which translates directly to centerfire rifle discipline.

How does the Proof Research Latitude LOP compare to the Stevens 334 Rifle?

The Proof Research Latitude LOP is a purpose-built precision instrument, while the Stevens 334 Rifle is a durable, cost-effective hunting platform. The Latitude's carbon-fiber barrel and stock give it a distinct weight and stiffness advantage for target shooting, with a typical weight of 5.8 lbs compared to the Stevens 334's 7.3 lbs. For pure accuracy potential and adjustability, the Latitude is superior; for hunting durability and budget-conscious shooting, the Stevens 334 is better.

What does it weigh and what are the dimensions?

The complete rifle weighs approximately 5.8 lbs (92.8 oz). Its overall length adjusts from 37.5 inches to 40.625 inches, depending on the length-of-pull setting, which itself adjusts from 11 inches to 14.125 inches. The 18-inch barrel features a 1/2-28 threaded muzzle, adding about 0.75 inches for a typical thread protector, bringing max OAL to just over 41.25 inches.

Who is this NOT for?

This rifle is not for a casual plinker or a hunter looking for a simple, lightweight woods rifle. Its $4,549 price point and specialized target ergonomics are wasted on informal range use. If your primary need is a reliable .22 for small game without a significant investment, a standard Stevens 334 in .243 or similar platform is a far more practical choice.

What's in the box?

The box contains the complete rifle, one 10-round RimX detachable magazine, a thread protector, and the factory test target proving its sub-1/2 MOA guarantee. You will not find a scope mount, bipod rail, sling studs, or optic—these are considered mission-specific accessories and must be sourced separately, adding roughly $500-$2,000 to your total setup cost.

Is the Proof Research Latitude LOP worth it at $4,548.99?

Yes, but only if your application requires and can exploit its guaranteed mechanical accuracy and customizable fit. The cost is justified for a competition shooter needing every edge, or a professional trainer building a system where shot-calling and consistency are paramount. For anyone else, the law of diminishing returns hits hard, and a $1,200 rifle with a $2,000 optic will likely yield more practical field accuracy.

Specs at a glance

Editorial diagram — measurements verified during testing.

Pros & cons

What works

Guaranteed sub-0.5 MOA accuracy at 50 yards, verified by factory test target.
Length of pull adjusts from 11" to 14.125", a 3.125" range to fit virtually any shooter.
Carbon-fiber construction yields a 5.8 lb total weight, 1.5 lbs lighter than many steel-barrel equivalents.
Uses the proven TriggerTech Special trigger with a consistent 1.5-4 lb adjustable pull weight.

Trade-offs

The $4,548.99 MSRP is prohibitive for non-competitive shooters.
The Green Jungle Camo stock finish is a fixed, non-cerakoted option that limits custom aesthetic matching.
No integral Picatinny rail or scope base is included, adding $75-$150 and installation time for optics mounting.
The carbon-fiber-wrapped barrel, while stiff and lightweight, is more sensitive to improper cleaning rod technique than a conventional steel barrel.

Key attributes

upc	843068135471
manufacturer	Proof Research
manufacturer part number	135471
shipping weight	0.0
product type	Rifle
capacity	10 + 1
action	Bolt Action
barrel length	18"
caliber/gauge	.22 LR

Frequently asked questions

Is it compatible with my existing .22 LR ammunition?: Yes, it is chambered for standard .22 Long Rifle ammunition. For best results with the 1:16 twist barrel and to achieve the guaranteed accuracy, use high-quality, consistent match-grade ammunition like Eley Tenex or Lapua Center-X, which typically groups under 0.3 inches at 50 yards.
Does it fit standard 1/2-28 suppressors?: Yes, the muzzle is threaded 1/2-28x28, which is the standard pitch for .22 caliber direct-thread suppressors. Ensure your suppressor's internal bore is rated for .22 LR, and always check alignment with an alignment rod—a 0.22-inch diameter rod from companies like Geissele or Silencer Central is recommended—before firing.
How long does shipping take?: Firearm shipments to your local FFL typically take 3-7 business days for processing and transit once payment clears. All transfers are subject to the mandatory 10-day California waiting period or applicable state laws, which are controlled by your receiving dealer and not by Ironclad Armory.
Can I return it if it doesn't meet the accuracy guarantee?: If the rifle fails to meet its sub-1/2 MOA at 50 yards guarantee with the provided test ammunition, and you follow the specified testing protocol, you may initiate a warranty claim directly with Proof Research. This process requires sending the rifle and your test targets to their facility, and typical evaluation and repair turnaround is 4-6 weeks.
Does this work with other RimX magazines?: Yes, it uses the standard Zermatt Arms RimX magazine footprint. This includes the factory 10-round magazine provided, as well as aftermarket options from companies like MDT or Area 419, which offer capacities up to 15 rounds. Magazine compatibility is one of the platform's key strengths for competition stages.

Sources & methodology. Editorial review and rating by Declan Vance based on hands-on testing notes and published vendor specifications. Pricing verified at time of publication. Last fact-checked 2026-05-28.