How to make muzzleflashes be in the right place?

Well, I’m working on a Swep pack, my 3rd one, and I really need to learn how to make the muzzle flashes be in the right place.

So can anyone help me?

Can someone please help me with this?

I would think that it is more of a problem with the model itself (its attachments, to be more precise), but I am not entirely certain.