Anyone use magnum primers for reloading .308 Win

I don't load .308, but they will work fine. As with any component change, drop and work back up.


Caution given, I've not seen any dangerous changes by going to a mag primer with an otherwise sensible load, and I've experimented a bit. Out here you use what you get, so best to get an idea what will happen when your not scrambling for components.

just drop back about 2 tenths of a grain you'll be fine!

I use Mag Primers in both, I suggest reducing powder by 10% to start.

good luck
Dan

LoonWulf said:

I don't load .308

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Communist!

But back to the topic, mag primers are often recommended in various reloading manuals when using ball powder. I’ve used them and didn’t see much of a difference.

I’ve also tried SR mag primers in my 6BRA because others have had better accuracy using them in that cartridge. I didn’t get those results but there was no difference in measuring FPS vs non-mag primers

EMT40SW said:

My LGS Was shutting down so I got a deal on CCI 250 magnum primers for $25/1000 primers. My question is does anyone use magnum primers for .308 or .30-06?

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Yes, I use magnum primers in both my 308 Winchesters and my 30-06s, as well as my wife's 7mm-08s. As a matter of fact, I don't think any of those rifles have ever seen a non-magnum primer. Magnum primers (mostly CCI 250s) work swell in those rifles, but again, I worked up the loads for those rifles from the start using magnum primers. If the loads you've already worked up are pushing close to max, you might have to back off powder charges by a couple of grains.

Once long ago I had a hang fire in my 7mm RM while hunting in sub zero temps and ever sense then all I purchase is CCI mag large rifle primers so anything that takes LR gets a mag primer. I wasn't until the Obama shortage that I purchased non mag primers in SR, SP and LP before them all I loaded in any round was a mag primer. Now I keep a few 1000 around for plinking loads for SR, SP and LP.

Only time I have ever had an issue with mag primers is in my Ruger 204, just couldn't get the rifle to shoot under 1/2" at 100 yards, one day I was reading some info about mag primers causing accuracy issues in small cases so I loaded up some loads with standard CCI primers and sure enough the 1/2" load shrunk down to less then a 1/4" load at 100 yards.

Over the years, I've done 3-4 experiments on magnum/non-magum powders in cartridges in the 308 to 30-06 range. Carefully controlling temperature, I have yet to find any difference in pressure or muzzle velocity. It doesn't mean there is no difference--just that it wasn't detectable in the loads I was experimenting with.

Nature Boy said:

Communist!

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Nuh, Uh! I have ...wait...no my buddy has my 06 now....

Actually I lied, I do load 308, but not for my own guns, so follow book loads to the letter.

As a new reloader in the current market availability of components I appreciate threads like this! I have a hodgepodge of primer types and sizes (except small rifle & small rifle magnum, I don't own any rifles whose cartridges us that size primer).

I sent a query to Hodgdon a few months ago after studying a few Speer Reloading Manuals I'd picked up that recommend magnum primers in general with ball powders, but not seeing magnum primers in the online Winchester StaBALL 6.5 powder load data. Plus certain brands, CCI in particular, were more readily available in my area. Their "official" answer was primer brands could be substituted in same size and rating (like CCI #200 for Remington 9.5) but to never to use a magnum primer unless specified in the load data, because modern primers work better these days.

The analytical part of my mind questioned if worked up from the starting load value, surely it wouldn't be unsafe at the start point and the same criteria for reading pressure signs would apply regardless of primer size used as the load is increased from the start value. Y'all have validated my train of thought, plus given me good first hand user info for in case I develop a load with standard primers, but only Magnum primers become available, I could reduce the load somewhat and work back up. My thanks!

I know the actual manuals say even substuting same size & type of primer to drop back to the start load level and work up but dropping back all the way to the start value seems extreme especially with centerfire rifle cartridges I use, primarily the 30-06 and 308 case size families. Dropping back a lesser amount for that also seems reasonable.

denton said:

Over the years, I've done 3-4 experiments on magnum/non-magum powders in cartridges in the 308 to 30-06 range. Carefully controlling temperature, I have yet to find any difference in pressure or muzzle velocity. It doesn't mean there is no difference--just that it wasn't detectable in the loads I was experimenting with.

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This mirrors my experience. Negligible differences in rifle loads.

Now when you get to pistol loads, I have seen a difference on target switching between magnum and standard primers with some calibers.

LoonWulf covered it in this [censored] post.

LoonWulf said:

...they will work fine. As with any component change, drop and work back up.


Caution given, I've not seen any dangerous changes by going to a mag primer with an otherwise sensible load, and I've experimented a bit. Out here you use what you get, so best to get an idea what will happen when your not scrambling for components.

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@Nature Boy , not a communist but I don't load the wimpy 308 only the 30-06. It is okay to use the magnums just work your loads up as has been suggest

Unless you are pushing a max load, I don't suspect it will make much of a difference. I have done it in the past when mag primers was all that I had.

I load -06 more than .308, and use mag primers for ball powders and for a reduced load that I like. I'm thinking that the hotter spark will result in more consistent ignition with a shifting powder charge.

It depends on the powder. If it's an IMR type powder or Varget I'll use standard large rifle primers. If I'm using Winchester 748 that's one powder my reloading manual recommends using magnum rifle primers with. It doesn't burn clean when you're using standard large rifle primers.

.308 Norma said:

Yes, I use magnum primers in both my 308 Winchesters and my 30-06s, as well as my wife's 7mm-08s. As a matter of fact, I don't think any of those rifles have ever seen a non-magnum primer. Magnum primers (mostly CCI 250s) work swell in those rifles, but again, I worked up the loads for those rifles from the start using magnum primers. If the loads you've already worked up are pushing close to max, you might have to back off powder charges by a couple of grains.

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Is there a reason you've only used magnum primers? Or is it more a case of "that's what I had so I rolled with it"?

i use mag primers in both without any problems. i use mag rifle primers in all of my loads with out any problems. i have done test between mag and standard primers with pistol and rifle. some powders will give 50 fps more with mag primers, but most are around 25 fsp. i got a 357 mag titegroup load were the mag primer give me 12 fps more. any load that you do you should work the load up to make sure your load is safe. a chronograph is your friend when you are load testing.

According to my best guestimation (min. 100 rds/week for 18 years), I've loaded and fired at least 85K rounds of 30-06 and 308 handloaded ammo and never used a magnum primer in those calibers. Probably 1/3 of those were WW748, BallC and my all time favorite long range 30-06 powder, H450. Never had any ignition problems w/ball powder, but never shot in extreme cold temperatures.

Fed. 210's and Benchrest primers seemed to provide pretty uniform ignition with stick and ball powders alike, based on the accuracy achieved w/these target rounds.

WW 748 Ball Powder V 600 yd reduced to 100 yd targets V..H 4895........H450 Ball Powder 30-06 V


Magnum primers would work find for either cartridge, but, in an abundance of caution I'd cut back loads developed with standard primers and work back up as suggested by others.

Regards,
hps

CptnAwesome said:

Is there a reason you've only used magnum primers? Or is it more a case of "that's what I had so I rolled with it"?

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Both, actually. Although, my only having magnum primers on hand for our big game hunting rifles was sort of a self-imposed restriction. I’d read in my handloading manuals how magnum primers provide better ignition in very cold weather, and it can be very cold indeed during deer and elk season here in Idaho. So, when I was only loading for our big game hunting rifles, I only kept magnum rifle primers on hand - they don’t cost much more, I’ve always been able to work up acceptably accurate big game hunting loads with them, and they work regardless of whether it’s 15 degrees and snowing, or 80 degrees and sunny.
That said, I have both non-magnum and magnum, small rifle and large rifle primers on hand nowadays. But that’s because I load for a greater variety of rifles than I did 30 years ago. Besides, my wife and I don’t hunt as hard as we used to. We can’t - especially if it’s snowy and cold.