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You aren't going to get 1/4 MOA groups or anything. Are you talking smokeless or black? 577/450 or .303?
For shooting black powder large pistol primers work great but if you have large rifle handy feel free to use them. For smokeless you might get better results with the large rifle but it will depend on the powder.
If you do get to the point of serious long range shooting or competition you will have learned what works for you by then.