Using Magnum Rifle Primers in a 308

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Depends on the powder you use whether on not the calibers last designation is "magnum" or not.

Generally charges of ball/sperical powder need magnum primers, as well as large charge weights in general. Check a current manual for the correct powder/primer combos.
 
Winchester 748, 760 are ball powders and they are among the best powders for .308win. No magnum primer is needed in the .308win. cartridge. There are about 50 different powders that work well in the .308win. It is not persnikety about the powder that it uses however, different powders work better with certain weight bullets. BL-C(2) seems to work best with a 175gr. bullet and 185gr.- 190gr. bullets. In the link below, any of the listed powders will work with the bullet weight that you highlight as long as you stay within the minimum/maximum charge weights listed. The highlighted powder and bullet combination in the link will show what the author found worked the best.

http://stevespages.com/308_13_165.html
 
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Reason I ask is a local gunshop owner advised me on the mag primers, but up to this point I'd been buying regular large rifle primers. If it works and doesn't affect accuracy at this point, that's really all I care. I take it I'm good with the mag primers?
 
You shouldn't need a magnum primer for that load. But if that's all you have reduce the powder by 10% and work your way back up.
 
Actually, CCI 250 large rifle magnum primers seem to work better in my 308 with IMR 4064 and it's not a ball powder.
 
People who understand what's needed for best accuracy and win rifle matches setting occasional records along the way use mild primers. There's too much variance in the magnum ones for best accuracy. These guys don't use ball powder either. It's never shot as accurate as extruded powder in the .308 or any other cartridge as far as I know.

A friend of mine years ago tested all sorts of primers in a .17 Rem. case shooting BB's from powderless primed cases through a chronograph. Magmun primers shot BB's the fastest and also produced worst accuracy. Mild primers shot 'em the slowest and produced the best accuracy.

Primers in cartridges are like cue sticks on pool tables. Those gently used to start the powder (cue ball) doing its stuff end up with more accurate results down range (on the table).
 
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Yep, the Benchresters of old lamented when they changed the priming compounds. The newer compound was much stronger. I have always been told by benchresters/target shooters that the mildest primer that will do the job is the right one for accuracy.
 
Walkalong, did you know that back in the mid 1980's when the Eley .22 rimfire ammo plant had a big explosion in their primer mixing and inserting section killing a few workers? They changed it's formula to new one with different compounding and more glass frit in it.

Accuracy with their best ammo hasn't been as good as it used to be. Virtually all of the .22 rimfire records established prior to that still stand. And barrel life was about half as much with their new priming formula. Some improvements have been made but I don't think they've caught up to pre-1985 levels.
 
Interesting.

I do not keep up with .22 rimfire, although I have thought about trying .22 Benchrest. There are matches locally, and the folks I shot Benchrest with who were shooting it as well said it was even tougher. It would be fun I am sure. I have been so busy with childrens needs I have not been able to travel and shoot any benchrest in a while. I miss the competition. My youngest may be out of the house soon, and I will have more time.

Alan Hall is close to me, and he shoots matches at our local club. Great guy. I need to get off my duff, stop thinking about it, and get a rifle to get started. :)
 
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