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Topic: Magnum vs Standard primers, effect on pressure (Read 217 times) previous topic - next topic

Magnum vs Standard primers, effect on pressure

New member here. New to the forum and newish to reloading for the rifle. If this is already been covered, please excuse me.

In general what is the difference in internal ballistics, specifically pressure and powder burn rate, of using magnum primers in loads developed for standard primers, all else being equal? Do I need to alter published load data to compensate for the extra oompf of the magnums?

TIA,
Dave

Re: Magnum vs Standard primers, effect on pressure

Reply #1
You may not experience much increase in pressure or velocity at all.  If you test a switch I would drop the charge a tenth or two of a grain to be sure but if you are not running your current load on the edge you can go with your current load and see if your gun likes them.

Re: Magnum vs Standard primers, effect on pressure

Reply #2
I switched to magnum primers for the 6.5 and find not much difference in pressure with maybe 1/10 or so less powder as rardoin did. I did so because Hornady used magnum primers for their data and I use some ball powder that recommend magnum. My general feeling is they give me more consistency and that is what I shoot for in all aspects of loading.

Re: Magnum vs Standard primers, effect on pressure

Reply #3
In my hornady manual they use federal 210match primers. Not magnum. Just to clear that up.
Grant


Re: Magnum vs Standard primers, effect on pressure

Reply #5

1) In general what is the difference in internal ballistics, specifically pressure and powder burn rate, of using magnum primers in loads developed for standard primers, all else being equal?
2)Do I need to alter published load data to compensate for the extra oompf of the magnums?

TIA,
Dave
1) In general, there is zero difference; especially when using powders that are temp stable. Despite hollow marketing claims by Hodgdon, there are a ton of them out there; many of which are ball powders.
2) Generally speaking, output isn't much different in totality, but the hot metallic particle output may be different. There is more difference between brand, than simply mag Vs. standard.  To hopefully explain this better think of a set of primers (1 STD, 1 mag) which both put out 1,000° and 300 joules of energy. The standard ignites properly, but puts out 0.01 grams of hot metal particles. The mag is only different on the metal output of 0.02 grams.

Unless you actually use pressure measurement equipment, there is no amount of "signs", prayers, or Chrono data that will honestly inform you of real world differences.

My phone is about dead, but I'll try and remember to post some pressure tests later.

Cheers
I'm a firm believer in the theory that if it bleeds, I can kill it.

Re: Magnum vs Standard primers, effect on pressure

Reply #6
Small rifle

Large rifle
I'm a firm believer in the theory that if it bleeds, I can kill it.

Re: Magnum vs Standard primers, effect on pressure

Reply #7
In my hornady manual they use federal 210match primers. Not magnum. Just to clear that up.
Not being familiar with Federal I thought the m was for magnum not match, my mistake. Do you know if the 210m is hotter than the standard or?