I've got some magnum rifle primers and am thinking about trying some with some 270 loads. I have both IMR 4350 and 4831 powders. What is the rule of thumb about using magnum primers with standard loads that everyone is using? Reduction by how much? I have the primers, and no magnum calibre's so I thought I'd use them and see what the results are. Thanks guys!!!
270 Loads with Magnum Primers
- Thread starter Henry45
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If you are not running near MAX loads, you may not have to back off at all-but to be on the safe side need to back off a couple grains and work back up IMO.
I've started using CCI mil primers for all rifle loads and they are magnum primers according to the website. I don't run MAX and basically wound up working right back to my old loads with no change. Different brands may be hotter.
I've started using CCI mil primers for all rifle loads and they are magnum primers according to the website. I don't run MAX and basically wound up working right back to my old loads with no change. Different brands may be hotter.
FROGO207
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They MAY/COULD have a bit more brissance than a regular primer and therefore burn a bit hotter/longer. They are often used with ball propellants to assure good ignition in colder weather as a rule. I have just subbed them in at STARTING loads and worked up as usual in several rifle calibers with good results. Just be aware that the published MAX load may be too much when using them in this way. If you find a good load on the lower side of load data all the better. I would also test the loads in HOT weather as well before calling them safe.YMMV
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