JSB King Heavy MK2 .25 | 33.95 gr. | 300pcs

High-Performance. Magazine Friendly. Built for the Long Game.

The JSB Match Diabolo Exact King MKII Heavy is a purpose-built heavyweight .25 caliber pellet engineered for high-performance airguns, long-range shooting, and hunting larger game. At 33.95 grains with a domed round-nose profile and a refined MKII skirt design, this pellet delivers the aerodynamic performance, consistency, and magazine compatibility that serious .25 caliber airgunners demand.

Overview

The King MKII Heavy builds on the proven original King Heavy platform with one key refinement — a reduced skirt diameter of 6.5mm compared to the original MKI's 6.68–6.70mm. This smaller skirt profile feeds more reliably through rotary magazines without compromising the pellet's flight characteristics or terminal performance. The domed round-nose design enhances aerodynamics for high-velocity performance, strong energy retention at distance, and reliable impact on larger game. Each 300-count tin is held to JSB's famously tight manufacturing tolerances for consistent, repeatable results shot after shot.

Key Features

• .25 caliber heavyweight domed pellet engineered for high-performance airguns
• 33.95gr design delivers substantial downrange energy for long-range shooting and larger game hunting
• MKII reduced skirt diameter (6.5mm) for improved rotary magazine compatibility
• Domed round-nose profile enhances aerodynamics for high velocity and consistent accuracy
• 300-count tin for extended range and hunting sessions
• JSB's industry-leading manufacturing tolerances for shot-to-shot consistency
• High ballistic coefficient of 0.054 (GA) for predictable, stable long-range trajectories
  
  

MKII vs. MKI — What's the Difference?

The only difference between the King Heavy MKI and King Heavy MKII is the skirt diameter. The MKII skirt measures 6.58–6.60mm compared to the MKI's 6.68–6.70mm — making the MKII more reliable in rotary magazine-fed airguns. Flight characteristics and terminal performance remain the same. Note that skirt appearance may vary between production runs.

Performance Advantage

• Reduced MKII skirt diameter feeds more reliably in rotary magazines on high-performance .25 caliber platforms
• Heavyweight 33.95gr design retains energy effectively at extended ranges for confident long-range shooting
• Ballistic coefficient of 0.054 (GA) delivers one of the flattest, most stable trajectories in the .25 caliber pellet category
• Domed profile balances aerodynamic efficiency with reliable penetration and energy transfer on impact
• JSB's tight tolerances minimize fliers and maintain consistent groups across the full tin
  
  

Specifications