M4 (T.Marui) Ø6.03 Copper Inner Barrel (345mm) for GBB 13.5" barrel

This 6.03 precision tight-bore upgrade inner barrel is made by CNC process.

This 345mm length inner barrel is specially made for M4 (T.Marui) GBB with 13.5” outer barrel.  While it provides tighter grouping and higher accuracy shooting, it offers best hop-up performance for longer shooting range.

All products are for airsoft only.  They are not made for real steel firearms.