M4 help !

[ariamark]

Right so IAM trying to remove the outer barrel on my g&p m4 I've done it before and had no problems , but hen I gave it to **** ******* to do a bunch of upgrades to they must of tightened the shit out of it or something because I can get the barrel nut off , IAM thinking of putting the gun in a vice and using a wrench, so my question in , how do I grip a m4 in a vice without damaging it and has anyone got any ways off taking the barrel nut off without a armorers wrench ?

Thanks
Ariamark
Peace.