Standard/Magnum Primers?

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I'm just checking to see how many guys use magnum primers in standard cartridges, ie: 243 on up to 30-06. Any difference in accuracy or pressure?
 
I’d say it’s worth trying both. I use CCI450 in both 6.5CM and 6BRA loading both extruded and ball powders. I chose to run magnums is twofold. My loads are on the warmer side (harder cups) and I shoot in colder weather(reliable ignition). I’d say test both and let the target be the judge. Standard primers do have softer cups so if you start to see flattened or pierced primers; you may not have a choice and will need to explore different options.
 
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I use LRM primers in the X57 case cartridges, not sure why but I have experienced more consistent ignition, particularly in cold weather. I don't think you will get much improvement of ignition in the .308 case cartridges, but quite possibly in the /06 case, particularly with ball powders. Is your question regarding improved ignition or a shortage of LR primers?
 
I have been contemplating using magnum primers in standard cartridges because I'm running out of of standard primers and have lots of magnums.

This is why I asked the question, running low on Federal 210's. I did purchase 400 large rifle Bosnian primers from the nice gentleman who ownes Budget Shooters Supply. I could of purchased more however, I heard that it is hit and miss with these primers plus, they are more difficult to seat in the primer pocket.

My 240 Wby., 270 Win. and 30-06 are just at max load and hesitant of compromising the loads and rifles. The easy fix is to locate Fed. 210's however, they are rediculously overpriced from greedflation sellers.
 
This is why I asked the question, running low on Federal 210's. I did purchase 400 large rifle Bosnian primers from the nice gentleman who ownes Budget Shooters Supply. I could of purchased more however, I heard that it is hit and miss with these primers plus, they are more difficult to seat in the primer pocket.

My 240 Wby., 270 Win. and 30-06 are just at max load and hesitant of compromising the loads and rifles. The easy fix is to locate Fed. 210's however, they are rediculously overpriced from greedflation sellers.

I also bought some Bosnian primers to try, I'm just not holding my breath they will be the same quality.
 
Reduce you powder charge by 1 grain if you switch to magnum primers.

Not necessary in any of my testing... I have tested loads with LR and LRM primers in many cartridges, ie. 6.5 Rem Mag, 7X57, 7X64, 7.62X57, .30/06, .358 Win, .35 Whelen, .450 Marlin, .45/70... exactly the same POI in every case.
 
Not necessary in any of my testing... I have tested loads with LR and LRM primers in many cartridges, ie. 6.5 Rem Mag, 7X57, 7X64, 7.62X57, .30/06, .358 Win, .35 Whelen, .450 Marlin, .45/70... exactly the same POI in every case.

I'll ssume that you had no pressure issues. I'll have to load-up three rounds for each cartridge with LRM primers, to test for pressure, POI and groups. I won't take components for granted anymore, lesson learned!
 
I'll ssume that you had no pressure issues. I'll have to load-up three rounds for each cartridge with LRM primers, to test for pressure, POI and groups. I won't take components for granted anymore, lesson learned!

Nobody should take it for granted, always work up... but my experience netted zero difference on target.
 
On average switch to a magnum primer is about 30 fps, or 1 grain of powder. If your load was POI sensitive to load changes during the work up process, then swapping primers might not be doing your rifle any favours. Damn whippy barrels, but enough about my morning. :( Accuracy is a crap shoot, your load might fall apart or you may notice no difference at all. Theres only one way to find out, good luck.
 
I'm just checking to see how many guys use magnum primers in standard cartridges, ie: 243 on up to 30-06. Any difference in accuracy or pressure?

Yes there will be an increase in pressure with magnum primers. More pop means more pressure. So as others have already mentioned, start at the bottom of the charge weight reloading manual spec's, and work up carefully (which is normal operating procedure anyways :) )

I have no experience with LRP's for standard vs magnum. However I have alot of experience loading with small rifle primers and comparing standard vs magnum SRP's in Lapua brass, 6.5 x 47 Lapua. I posted data and a graph of chronograph results for load work-ups in post #17 of this thread, comparing MV's:
https://www.canadiangunnutz.com/forum/showthread.php/2292869-123Gr-Scenar-for-6-5-Lapua/page2

The higher velocities per charge weight using the magnum primers mean higher pressures per charge weight. All my testing was well within safe pressures. Just use your normal safety protocols and observations for pressure signs, as per the reloading manual instructions, and you should be fine.

Note: Pressure signs may not always be detectable by eye. A good surrogate for staying within safe pressure is to stay within (under) the manual's published max velocity for the specific bullet weight and powder brand. Those published max velocities correlate directly with max pressures, because velocity is the direct result of pressure. A chronograph is your best friend for doing these work ups.
 
There never is any signs until there is.

There wasn't... primer pockets tight after firing, easy bolt lift, no stretching of the brass, no failed cases... exactly the same condition whether loaded with LR or LRM... you do you... as always... work up your own loads.
 
I'm just checking to see how many guys use magnum primers in standard cartridges, ie: 243 on up to 30-06. Any difference in accuracy or pressure?

It was more of a concern for me when I lived in the arctic. The theory being that a magnum primer will help ignite the powder charge in extremely cold weather. Not sure if it really makes a big difference, I didn't ever compare loads over the chrony between summer load development and some of the hellishly cold winter weather. That would make an interesting experiment though. To my recollection, I only did so in the 30-06 and not in the 308, 25-06, or 9.3x62.
 
I only use magnum primers for my sons 300 win mag, and that is because I have some on hand that I got in a purchase that had a bunch included them.
I have seen no need to use them and have to work up a new load for the 243, 270, or 30.06.
I used them when I started loading for the 300 .
 
At the risk of dating myself I will say that about 45 years ago when I started reloading there was an old boy that had been reloading for many years and I asked him this very question, he simply said rule of thumb is 60 gr or less standard primer 60gr or more magnum primer, new and more technically advanced cartridges, powders and primers have come along as have studies by gun writers, then of course came sponsored you tube and podcasts all of which have changed peoples views on what works best, not necessarily for the better, to each his own no matter which one you choose start low and go slow when working up a load, the way supply is these days use what you have on hand it will all work.
 
I’ve been using both in 6.5 PRC, 6.5 CM and only thing I’ve noticed is the LRP is a little more accurate than the magnum primers.

I also have a few bricks of Sellior&Ballot that’s labeled for use in large rifle or large rifle magnum .
 
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