The PDI-Japan 230mm 6.01 inner barrel for the Maruzen CA870 series is constructed from durable stainless steel (SUS304). The company says its exceptionally tight 6.01mm inner diameter is engineered to minimize air loss, resulting in excellent momentum transfer for the BB as it's propelled forward. This characteristic makes it optimally suited for short-range engagements, such as those encountered with pistols.

Confused on wide bore and tight bore inner barrels for use in airsoft guns? Mark Carico helps out in this video to give you a better understanding... "In this I am discussing the differences in wide bore vs tight bore barrels and long vs short barrels to hopefully help clear up some questions."

Take your pick of inner barrels produced by PDI Japan for the KSC HK33 series. Diameters available are 6.01, 6.03, 6.05, 6.08, and 6.15. The outer diameter is 8.55 and tolerance is ±0.002mm. The inner barrels are made of SUS304, a common austenitic stainless steel that offers a balanced combination of corrosion resistance, toughness, ductility, machinability, and weldability, making it a highly versatile material suitable for diverse applications. Compatible models are the KSC HK33A3, HK33A2, and HK33K.

Tech tutorial by Combat Sport Supply where they show how you can install a tightbore inner barrel... "Airsoft Tightbore Barrels improve Accuracy, FPS and Range, but How Do You Install a Tightbore Barrel? We Guide You Step by Step on How to Properly Install an Airsoft Tightbore Barrel here."

Laylax got this video out for those who want to replace the inner barrel of the Krytac KRISS Vector gas blowback SMG. The high-precision inner barrel under the Nineball brand is crafted from rigid stainless steel, boasts a dimensional accuracy of 1/100 mm, ensuring a snug fit for BB bullets and preventing any shaking. With an inner diameter of φ6.03 mm and a total length of 120 mm, this meticulously engineered barrel aims for optimal performance and accuracy.

The new PDI RAVEN 6.01+ Inner Barrel for the Tokyo Marui VSR-10 G-SPEC airsoft sniper rifle is now available at the X-Fire online store. This CS barrel offers a more affordable alternative to our premium SUS barrels while still delivering impressive performance. With an inner diameter of 6.01mm+, the RAVEN barrel provides high FPS and accurate shots.

Jaeger Precision has upgraded the Tokyo Marui LCP 2 inner barrel with a PDI 6.01 inner barrel. The 6.01mm diameter offers a tight fit, resulting in minimal air loss and excellent momentum for short-range shooting. However, this precision comes at the cost of a less stable flight path compared to wider barrels. It's crucial to use high-quality BBs and maintain the barrel regularly to prevent scratches or jams caused by wax or dust.

A howto video released by Wyhaq to help guide owners of the Umarex Glock Gen 5 GBB pistols to change the inner barrel and bucking... "In this video, I show how replace or change or upgrade the inner barrel and bucking on officially licensed Glock airsoft replicas. This is a very easy guide and shows how the hop up works on these newer g-series replicas."

In this technical guide by YNS Tactical, they show how to disassemble the APFG MCX Hopup and Barrel... "This takedown and reassemble demo goes over some of the nuances with the APFG MCX line's front end, which includes the Hop Up chamber, mock gas block and adjustment dial, outer barrel, and muzzle device.

We demo a few solutions to help people prevent causing damage to this when taking them apart because it is something we see far too often.

The PDI Raven 6.01+ Inner Barrel is now available at the X-Fire online store for the Tokyo Marui VSR-10 G-Spec airsoft sniper rifle. This CS barrel, a more affordable option compared to their high-end SUS barrels, offers a 6.01mm+ inner diameter for increased FPS.