Advanced Reset Technology MP5-22 A.R.T. Lever w/ Buffer System - MP5

Advanced Reset Technology MP5-22 A.R.T. Lever w/ Buffer System

The Advanced Reset Technology MP5-22 A.R.T. Lever with Adjustable Buffer System is engineered specifically for the HK/Umarex MP5 .22LR platform. It installs into the factory trigger pack with only minor fitting and no permanent modification, allowing the existing trigger system to retain semi-automatic operation while adding an active mechanical reset between shots.

The included adjustable anti-bounce buffer system lets you tune bolt mass alongside the factory-adjustable recoil spring tension, helping improve bolt timing and cycling consistency across different .22LR ammunition types. The system is intended to help reduce bolt bounce and support more consistent operation once properly configured.

Features

• Designed specifically for HK / Umarex MP5 .22LR
• Installs into the factory trigger pack
• No proprietary housing required
• No permanent modification required
• Minor fitment may be necessary
• Active mechanical trigger reset
• Maintains one round per trigger pull
• Adjustable anti-bounce bolt weight system
• Works with factory recoil spring adjustment
• Supports tuning for subsonic, standard velocity, and high velocity .22LR
• Helps reduce bolt bounce and stabilize cycling
• Manufacturer’s Lifetime warranty

Specifications

• Manufacturer: Advanced Reset Technology
• Product Type: Active Reset Lever / Adjustable Buffer System
• Platform: HK / Umarex MP5 .22LR
• Operating Type: Semi-Automatic
• Trigger Reset: Mechanically Assisted
• Installation: Factory Trigger Pack
• Permanent Modification Required: No
• Fitment: Minor Fitment May Be Required
• Buffer Type: Adjustable Anti-Bounce
• Recoil Spring Adjustment: Uses Factory Adjustable System
• Suppressor Use: Not Recommended by Manufacturer

Ammunition Considerations

For best performance, standard-velocity .22LR ammunition typically performs extremely well once the system is properly tuned.

Certain ammunition types should be avoided, specifically:

• CCI Stingers
• CCI Mini-Mag
• Other extended-case .22LR cartridges

These rounds use longer casings than standard .22LR, which may prevent the round from fully seating in the MP5 .22LR chamber. Improper seating can cause the casing to bulge or split, resulting in an out-of-battery discharge & potentially a squib malfunction.

Always check your barrel after any malfunction.

For that reason, standard-length .22LR ammunition is strongly recommended. Once the system is properly tuned, standard-velocity CCI ammunition is the recommended choice for the most consistent and reliable performance.

Factory Extractor Considerations

Because of the operating characteristics of the .22LR MP5 platform, the factory extractor has been widely discussed in the builder community as occasionally contributing to reliability inconsistencies. Reported user observations have included:

• Extractor tension allowing the case rim to slip during cycling
• Cases hanging or deforming under certain ammunition pressures
•  In rare instances, reports of extractor engagement contributing to out-of-battery ignition events with a stock trigger installed

Because of these documented behaviors, the MP5-22 A.R.T. Lever system is designed to operate without the factory extractor, simplifying the platform’s cycling dynamics by removing an unpredictable variable.

Note: This system does not run well suppressed because of its low bolt weight.

Product Image Disclaimer: Product image is for reference only and may not depict the exact components included. This listing is for the MP5-22 A.R.T. Lever with Adjustable Buffer System only. Firearm shown is not included.