Re: Large rifle primer vs magnum
I don't believe you can generalize this. I have found primer type and brand differences to effect accuracy and ES. You need to test this with your specific caliber and load. Generally, you should get better and more consistent ignition with magnum primers in high capacity, magnum cases. I get much better ES in my 6.5-284 using Retumbo with Fed215's than with standard primers.
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