When used correctly, the conjunction "and" in "try and" means there are two distinct thoughts. If there is a continuous thought, always use "try to".
For example, in football a runner would try to score. He may or may not succeed. If you say "try and score" you are separating the try from the score. He is going to try and he is going to score. Since scoring is directly connected to what he is trying to do, the only correct way to say it or write it is "try to". They do not have the same meaning though some people use them as having the same meaning. You can prove this by using other tenses of try.
On that play the runner tried and score.
Obviously that does not work. It should be written as tried to.
The runner tried to score on that play.
The runner was trying to score.
Just because many people get it wrong does not make it right. Consider these two sentences:
The inventor will try to succeed in making his project work.
The inventor will try and succeed in making his project work.
They both could be correctly used but one means he may succeed while the other means he will try and he will succeed.