Unable to defeat last boss

[Freeman]

Hello guys ... im actually at the end of the game trying to defeat last boss... the boss fight is quite easy but I have a serious problem ... when he bang his hand on the ground and I manage to get on to his shoulder I cant shoot the doll in his pocket because my aiming is limited and when i lock the taret it lock him somwhere around his neck. I already tried it with every weapon but i just cant aim the doll ... any hint from you guys ? :-/ thanx

[Mulbruk]

Don't try to lock, just use a machine gun and spray in the general direction of his front pocket.

[Freeman]

OK i will try but i doubt it ll work ... i cant lower my weapon low enough ... hmm thank you for advice :)