Switching LR primers to magnum

[ECM4]

Ran out it Large Rifle Primers using superperformance powder. Would using Large Magnum Primers instead of regular primers change my load at all? Local gun shop only had magnum primers left. Or is This something you would have to start low and work your load back up.

 

[Unclenick]

It can. It can also either improve or worsen grouping, depending on load density and case capacity and powder. A good rule of thumb with primer change is to knock the powder charge down 5% and work back up to original velocity on your chronograph or to a best accuracy spot.

 

[hounddawg]

Simply switching brands of primers can affect the load, so yes. Follow Nicks advice