Magnum Primers for 303 British

[Eb1]

Would you use a Magnum Primer in 303 British? I think I would slack off the load a little, but I have a bunch that do not shoot good in my other rifles. So I was thinking of trying in the 303 British.

 

[Der Verge]

You are more than welcome to use magnum primers for that case. You must re work you loads back up though, as these primers WILL create higher pressures when used with the same amount of powder as in your regular loads.

 

[rcmodel]

The determining factor is what kind of powder you are using.

Ball powder = Mag primers.
Stick powder = Totally not necessary.

rcmodel

 

[Eb1]

rcmodel, I have heard that before, but I am finding when loading my 30-30 that the opposite seems to work better for me.

I had a load for my 30-30 that uses IMR4895. Was bad, but when I used a Mag primer. I closed up to an 1" MOA.

I had a load with another 30-30 using H335. Shot good, super good with LR primers. Started loading per the Speer Manual to use Mag primers. Load went to pot.

 

[Sunray]

Magnum primers burn a bit hotter for a bit longer. They're for igniting hard to light powders and for cold weather shooting. You don't need 'em for any .303 powder.