10.3''/10.5'' Outer barrel; Inner length
 

I'm changing my outer barrel for a 10.3 or 10.5 one, and I need i new inner barrel to fit inside.

I saw MadBull 300MM inner barrel on Airsofparts.ca. In the description, it says fit M4CQB length (probably with 10.5 barrel) , but 300mm is about 11,8 inches long... So it will probably not fit the 10.5 barrel, it will be visible inside the flash hider.

What is the best inner barrel length for 10.5/10.3 outer?

285mm is the correct length for 10.3 and 10.5" barrels. Some users run a 300mm if their flash-hider is long enough.

http://www.airsoftstore.ca/index.php...ex&cPath=35_33

Thank you Shealth, ordering from you monday =)
At the moment, I have a non-ported cylinder with a 363mm inner barrel
Moving to a 285mm inner, i'll need to change my cylinder. I need type 1 or type 2?

M4 hole (Type2)
or MP5 hole, although that's a bit more difficult to locate.