Magnum Primers needed???

[Rocky Raab]

This is yet another of those perennial Ford/Chevy questions to which there is no set answer.

In most cartridges, under most circumstances, with most powders and in most climate conditions, standard primers are perfectly adequate. But not all.

In most circumstances, with most loads, standard primers give smoother ignition and deliver cleaner burning, smaller pressure/velocity variations and better accuracy. But not all.

My general and entirely personal rules call for standard primers in all loads. But I shoot smallish cartridges in warm weather.

If your powder charge is larger than 65 grains, and especially if you use spherical powder, OR if you usually hunt/shoot when it's below zero temperature, then you MIGHT have better results with magnum primers. But it isn't guaranteed.

Some folks use magnum primers all the time; or always with spherical powders, no matter what case size or charge weight. That's OK, too.

The only firm rule is this: if you switch primers (or any other component) after working up a load to near maximum, you MUST back down the powder charge and re-test.

Bottom line? Your results may vary.