I took kicked Gabriel's ass with her own sniper rifle, as well as one of the high ammo snipers. The activation rate seems nice enough: I just went through that fight normally.
I hated that fight. Even the Final Boss was easier than her. Hell, even the bloody Worms, which are the bane of my existence, were easier than her. I just finished hard difficulty, what weapons are most effective on Deadly if I have infinite ammo?
Fan testimonials: Virtue777: Coolest guy/gal on the planet: http://www.gamefaqs.com/users/Xeedragon/boards Kewldude475: You...hav(e)...unfathomable skill.
If you're using infinite ammo then just pack a high powered sniper rifle, even on insane it drains her life bar fairly quickly. All you really need to worry about is just staying alive, not hard to do when you know what spots to hide in.
Playing: Resident Evil 4 HD, Muramasa the Demon Blade, Metroid Other M, Dragon Quest IX Sentinel of the Starry Skies. PSN: jext77
also awesome spot to grind. just have restock and a launcher. nuke the bees while trying not to kill off the main target. keep avoiding her otherwise. and of course, destroy the four or so bees that attempt to regenerate the main form whenever they attempt it.