Ive just bought a new brocock elite xl in .22 calibre. It held its zero for about 20 shots. After plinking in the garden with it to get used to the feel of it,it now shoots quite eratically.Ive made sure the barrel,barrel support and moderator are tight.Ive taken off the scope and remounted it. Then tried to zero it.Still eratic shots.I replaced the scope with a brand new mtc mamba lite and new mounts .Ive tried different pellets.Nope still no good .Im just about to send it back.Any help appreciated.