This is what is possible with a KJW M700:
-Custom modified M24 body from a Javelin M24 (CA M24 body is better)
-Spartan Doctrine VSR kit (Includes extended nozzle)
-G&G metal hop housing
-Polarstar bolt spring
-G&G Heavy fluted barrel (Very hard to find now, but free floats front barrel and is solid all the way through negating use of barrel spacers)
-Laylax steel 6.03 barrel
-Tanaka 29 round magazine tapped for Co2 rig in buttstock pouch using mini palmer regulator and 12g CO2 canisters.
-300 to 700 fps with .20 depending on regulator setting and bolt spring tension.