I just purchased a Handi-Rifle in .243 youth that came with a 4-12x40mm scope as part of a package deal and as long as the scope is on 4 power it is crystal but when I turn it to a higher power it blurs out totally. Any idea what the problem is? I was planning on putting a Nikon on it but if this one was as clear at the higher powers as at 4 power I wold keep it. This is for my 9 yo grandson by the way.