There are two approaches to your problem.. If you are shooting factory ammo, you might try different brands, as all primers are not of the same hardness or sensitivity. Another way to handle this with factory ammo is to go up about 1/4 turn and then try again. If you are punching paper, this should be sufficient. If you are hunting, another tweak of about 1/8 turn will insure ignition. Be aware that hunting in the cold will also cause misfires, so it is a good idea to build in a cushion with a little extra tension.
If you reload, then try different brands of primers and make sure that they are well seated. If you have access to a chronograph, test your loads for consistent velocities, as an overly light primer strike will cause variation.
