Hello everyone: I am a cashier at a grocery store so I have a lot of weird conversations with people. I got into a conversation with a regular customer about glocks and he was saying that they aren't good because the barrel is set in polymer or something and will mash the polymer after about 500 rounds. I am not sure what he is talking about and already have about 300 rounds through it with no signs of stopping. Anything I should look out for since this is my carry gun? I clean it every time I go out shooting.