Pingu.0211 does a comparison of inner barrels that can allow for a higher muzzle velocity for the Tokyo Marui MWS Gas Blowback Rifle. Covered in this video are inner barrels from Poseidon, Laylax, G&P, Lambda, and PDI-Japan... "Airsoft TM MWS GBBR Power upgrades! Discussing the intersection of Power, Accuracy and Precision.

Parts used:

• Poseidon Ice Pick Flute Valve High Power
• Laylax 370mm 6.03mm Tight bore MWS Inner Barrel
• G&P 410mm 6.03mm Stainless MWS Inner Barrel
• Lambda 425mm 6.05mm Micron Stainless MWS Inner Barrel
• PDI Raven 250mm 6.01mm GBBR Inner Barrel
• (Update PDI 304 steel 6.01 250mm has a tighter fit and will be around 365-375)"