Ruger Mark IV 22/45 .22 LR 4.4in Threaded Barrel, 2x10rd
About this product
What is the Ruger Mark IV 22/45? The Ruger Mark IV 22/45 is a .22 LR semi-automatic pistol engineered for precision rimfire shooting, suppressor use, and low-cost training with its 4.40-inch threaded barrel and one-button takedown system. It's built around a cold hammer-forged bull barrel that maintains consistent rifling over thousands of rounds, paired with a 1911-style grip angle that transitions seamlessly from training platforms to centerfire handguns. Compared to the Browning Buck Mark, which requires tools and partial disassembly for cleaning, the Ruger's takedown is a 2-second operation—just press the button at the rear of the receiver and the upper separates from the frame.
What is the Ruger Mark IV 22/45 used for?
This pistol is designed for suppressor-friendly rimfire shooting, low-recoil training, and introductory marksmanship, thanks to its threaded 1/2"-28 muzzle and .22 LR chambering. The 33.3-ounce weight provides stable offhand shooting, while the 4.40-inch bull barrel delivers 1.5-inch groups at 25 yards with standard velocity ammo. It's an ideal host for suppressors like the Dead Air Mask or Silencerco Sparrow, running sub-120 dB with subsonic rounds.
How does the Ruger Mark IV 22/45 compare to the Browning Buck Mark?
The Ruger Mark IV 22/45 outperforms the Browning Buck Mark in maintenance speed, with a one-button takedown that requires zero tools versus the Buck Mark's 15-minute field-strip procedure. However, the Buck Mark's factory trigger breaks cleaner at 2.5 pounds compared to the Ruger's 4.5-pound pull out of the box. For shooters prioritizing easy cleaning and suppressor compatibility, the Ruger is superior; for those wanting competition-level triggers straight from the factory, the Browning has the edge.
What does it weigh and what are the dimensions?
The pistol weighs 33.3 ounces unloaded and measures 8.50 inches in overall length with a 4.40-inch barrel. The grip circumference is 5.25 inches, fitting medium to large hands comfortably, while the Picatinny rail adds 0.5 inches of height for optic mounting. These dimensions make it 0.8 inches shorter than the Stevens 334 Rifle in .308 Winchester but balanced for one-handed use.
Who is this NOT for?
This isn't for buyers seeking a concealed carry weapon or high-capacity rimfire pistol, as its 10-round magazines and 8.50-inch length make it strictly a range or hunting sidearm. It also lacks night sights or optic-cut slides, requiring aftermarket plates for red dots—unlike dedicated competition .22s like the Volquartsen Scorpion. If you need immediate optics readiness or more than 10 rounds on tap, consider a different platform.
What's in the box?
You get the pistol, two 10-round magazines, a cable lock, and an owner's manual covering takedown and maintenance. Unlike some competitors, it doesn't include a thread protector or optic mount—those are separate purchases. Each magazine weighs 2.1 ounces empty and features a stainless steel body with a polymer follower for reliable feeding.
Is the Ruger Mark IV 22/45 worth it at $349.99?
At $349.99, it's fairly priced for a suppressor-ready .22 pistol with a cold hammer-forged barrel and modern takedown system. You're paying $50 less than the Browning Buck Mark URX but gaining faster maintenance and a more accessory-friendly rail. For rimfire trainers or shotgun companions like the Stevens 555 Sporting Compact, it's a logical add-on that won't break the bank.
Specs at a glance
Video review
Pros & cons
What works
- One-button takedown cleans in 15 seconds vs. 15 minutes for Browning Buck Mark
- 4.40-inch cold hammer-forged barrel holds 1.5 MOA with match ammo
- 33.3-ounce weight reduces fatigue during extended range sessions
- Picatinny rail accepts lights or optics without gunsmithing
Trade-offs
- Factory trigger breaks at 4.5 pounds—requires $120 Volquartsen kit for competition use
- No thread protector included—adds $15-25 aftermarket cost
- Blued finish shows wear after 500+ draws from kydex holsters
- 10-round magazines limit rapid-fire drill capacity compared to 15-round alternatives
Expert review
Key attributes
| upc | 736676401901 |
| manufacturer | Ruger / Sturm, Ruger & Co. |
| manufacturer part number | 40190 |
| action | Semi-Auto |
| atf type | Pistol |
| barrel length | 4.40" |
| caliber/gauge | .22 LR |
| capacity | 10 + 1 |
| color | Black |
| length | 12.3000 |
| model | Mark IV |
| number of magazines | 2 |
| package height | 3.8 |
| package width | 10.3 |
| product type | Pistol |
| safety | Ambidextrous |
| shipping weight | 3.6 |
| sights | Adjustable Rear Sight |
| sights type | ADJUSTABLE |
| state restriction (ca) | NO DIRECT SHIP TO CALIFORNIA |
Frequently asked questions
- Is it compatible with a suppressor?
- Yes, the 1/2"-28 threaded muzzle accepts standard .22 LR suppressors like the Dead Air Mask or Silencerco Sparrow. You'll need to verify your state's NFA regulations and submit a Form 4 through a licensed dealer, which typically takes 8-10 months for approval.
- Does it fit a Holosun 507C?
- Not directly—the Picatinny rail requires an adapter plate like the EGW Ruger Mark IV 507C mount, which adds 0.25 inches of height over bore. The Holosun 407K or 507K models are better suited for direct mounting with specific aftermarket optics bases.
- How long does shipping take?
- Firearms ship within 3 business days to your local FFL dealer after background check completion. Transit time varies by carrier, but expect 5-7 days for ground service via FedEx or UPS.
- Can I return it if it doesn't cycle ammo?
- Yes, within 30 days if unfired and in original packaging, but .22 LR ammo sensitivity is common—try CCI Mini-Mags or Aguila Super Extra before returning. Most cycling issues stem from underpowered rounds or dirty magazines.