I have 2 different injectors and both have 2 different needles, slanted tip needles and the others have several holes in the side. I inject cure or flavour mixes like Phil, insert the needle fully and slowly pull it out while pressing the plunger.
Sometimes you can get a gob full but not too often now as I press the meat with 2 fingers on both sides of the needle for a very short time.
Cheers,
Jan.