hey guys, i have a grey thats about 6years old. when i got him as a baby, he was hand reared and he was fine. however for the last 4 or 5 years he's got really aggressive. as soon i put my hand down for him to climb onto, he either bites (really hard) or backs away. i read up that you should not force it so i dont. a also tried not pulling my hand away when he does bite and sternly say "no!" but that doesnt help either. i aslo tried distracting him while putting my hand down for him to pearch on but that doesnt help either lol. please please please can you guys give me any suggestions??? thank you!!