Antitank Gun

How do I take a GECHO down(MGS4)?

I shoot them in the leg....the go down....but dont die......so i pull out all my guns including my rpg, antitank missle, sniper,m4, m64(very hard hitting machine gun) and even my grenade launcher(courtesy or raging raven).....but nothing seems to work
i jjust got the rail gun via crying wolf...will tht work as well?

when theyre down aim for the little ball on the top of them, i take them down with the 50cal sniper rifle all the time, theyre not invincible, you just need to take them down then destroy them, they have a few weak points, the m60 is a good choice for inflicting alot of damage as well

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