Burrs and irregularities can cause an uneven burn of the primer and thus the powder charge, causing velocity variations.

Check primer hole uniformity in bulletsCheck primer hole uniformity in bulletsCheck primer hole uniformity in bulletsCheck primer hole uniformity in bullets

  • Peter Lang

    There is a glaring error in the nomenclature used by the author and it would be better all round if the terms used are those which are correct standard practice.
    Bullets do not have primers in them, cartridges do.
    Bullets are those things that come out of the muzzle and the term does not apply to the loaded round which is a cartridge.
    It would be better if Mr Potts got his nomenclature correct and avoided sowing confusion amongst his readers.