M4 short outer barrel

[SGTSNIPER]

Ok so my thinking behind this is, take out the tb out off my s system, replace with either a cut down normal barrel 6.4 or a shorter tb barrel and attach a short outer barrel. the look im after is at the end of the hand guard i dont want 6in of outer barrel, but about an inch for the flip up site and the thread for the flash hader/ scilencer..:eek:.if you understand what i mean.a little bit like a CQB ftont end. can it be done and any advice on what type of barrel is needed...thanks mark