If your going to zero your rifle, after cleaning it, shooters in competitions are allowed 3 fouling shots before they get down to real shooting, clean it after every time you use it mate, same as any other gun. Keep the rifeling clean and it'll spin your bullet more effectively, so straighter shooting, So better accuracy, hope this helps.
PS
Every now and then, put some solvent designed for the job , down the tube to get all the copper residue out good and proper.
ATB
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