Our new stainless steel tightbore 6.02mm inner barrel. The hop window measures 6mm long and 4.5mm wide, these new inner barrels are specifically designed for hop rubbers which use larger contact patches such as the Maple Leaf MR. The extra length and width allows for a slightly larger hop rubber patch, best results are with buckings like the Maple Leaf MR together with a flat nub, like this combo:
https://www.ak2m4.co.uk/maple-leaf-mr-hop-rubber-60-flat-nub
These barrels are hand finished, inspected and then test fired to ensure a straight flight. Internal polishing is at the higher end, RA 0.5, as a comparison ZCI is RA 0.8-1.0, please check out the comparison video below.
* We clean and test each one before we send out, ensuring level flight.
* We offer a 30 day no-quibble returns policy should you experience any issues.
* Designed with larger patch hop rubbers in mind, such as the Maple Leaf MR - see link above for special combo.