Maple Leaf 6.02mm 91mm Nickel Plated Inner Barrel for G17/18, Desert Warrior, Hi-Capa 4.3, P226, Silver

The Maple Leaf 6.02mm inner barrel is a straightforward precision upgrade for your GBB pistol. The 6.02mm bore is tighter than the standard 6.03–6.04mm found in factory barrels, which reduces the gap between the BB and the inner wall. That tighter fit gives more consistent backspin from the hop-up and better shot-to-shot grouping, especially at the 100–150 foot range most pistols see.

What the 91mm length means. At 91mm this barrel fits compact GBB pistols like the G17, G18, Desert Warrior, Hi Capa 4.3, and P226. It is not a long-barrel build — you are not chasing range here. You are chasing consistency in CQB and close-quarters skirmish where a tighter group matters more than velocity.

Material and finish. The barrel is brass with a nickel plating, which is the standard for most GBB pistol upgrades. Brass is easy to machine and resists corrosion; the nickel plating adds a smooth surface that helps with BB travel. Maple Leaf barrels are known for consistent bore quality out of the box, so you are not relying on aftermarket tuning to get the benefit.

Installation. Swapping an inner barrel in a GBB pistol is typically a matter of removing the slide, taking out the hop-up unit, and sliding the old barrel out. The new one goes in the same way. You will need to re-zero your hop-up after installation, and you should test with your preferred BB weight to dial in the setting.

Before you buy, confirm that your pistol's outer barrel can accommodate a 91mm inner barrel. Some compact frames require shorter barrels, and a barrel that is too long will interfere with the slide or the hop-up assembly.

Includes only the inner barrel. Hop-up bucking, chamber, and installation tools are not included.