TACSOL PAC-LITE IV Ruger MKIV .22LR 4.5" Barrel - Black

The TacSol PAC-LITE IV upper assembly for Ruger MKIV .22LR rifles is a bolt-on upgrade that swaps out your factory upper receiver with a lightweight, more accurate alternative. If you shoot .22 at the range or in competition, or just want to squeeze better groups from your Ruger MKIV, this 4.5" barrel conversion delivers measurable improvements in handling and precision without requiring a gunsmith. The PAC-LITE IV's aluminum construction shaves weight, shifting the balance point forward for faster target transitions and less fatigue during extended shooting sessions.

The heart of this upgrade is a stainless steel breech face paired with an aluminum receiver and barrel, engineered to tighten tolerances and improve reliability compared to stock Ruger uppers. The barrel sports a 1:16 twist rate and 11-degree target crown, both designed to stabilize .22 rounds and promote consistent accuracy. Threading is standard .22 x 28, and it ships with a thread protector cap. Installation is straightforward—the upper slides onto your existing Ruger MKIV frame without disassembly tools or professional help, making this a practical afternoon upgrade for shooters who want better performance without the gunsmith bill.

The 4.5" barrel length keeps the rifle handy for bench shooting, plinking, or competition formats where barrel length matters. The receiver is drilled and tapped for PAC-LITE scope bases, so you can mount glass without adapter rings. For .22LR shooters building a tack-driving Ruger MKIV or refreshing an older gun, the PAC-LITE IV is a direct path to lighter recoil, faster handling, and groups that prove the upgrade pays for itself in satisfaction.

Key Features

• Drop-in upper assembly for Ruger MKIV and MKIV 22/45 frames—no gunsmith required
• Stainless steel breech face and receiver for improved reliability and tighter tolerances
• Lightweight aluminum barrel and receiver reduce overall weight and improve balance
• 11-degree target crown optimized for .22LR accuracy
• 1:16 barrel twist stabilizes standard and high-velocity .22 ammunition
• Drilled and tapped for PAC-LITE scope bases
• Includes thread protector cap for .22 x 28 barrel threads
• 4.5" barrel length for range, competition, and tactical training

Specifications

Frequently Asked Questions

Will the PAC-LITE IV fit my Ruger MKIV or MKIV 22/45?

Yes. The PAC-LITE IV is designed as a drop-in upper assembly replacement for both the Ruger Mark IV and Mark IV 22/45. It installs on your existing frame without modification or gunsmith assistance.

Do I need a gunsmith to install this barrel?

No. The PAC-LITE IV upper swaps onto your Mark IV frame easily without special tools or professional installation. It's a user-friendly upgrade you can complete at home.

What scope base should I use?

The receiver is drilled and tapped to accept PAC-LITE scope bases. Standard Ruger MKIV bases are not compatible with this upper.

What's included in the box?

The PAC-LITE IV upper assembly ships with a thread protector cap for the barrel. You'll need to source a PAC-LITE compatible scope base separately if you plan to mount optics.