I'm new to the ak world and decided to enter it with a budget ak in the form of a psa gf3. Anyways, I notice when I shake it you can hear a rattling noise. Is this normal for aks? I completely field stripped it including the gas tube and it still has a small rattle to it. Is this normal or should I dig deeper at a possible issue with QC. I just want to make sure nothing is broken on it after it was shipped or of there is something I should be looking for.