Magnum primers for cold weather shooting?

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cheier

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I was curious about this. Doing my studying on gun powders and the reasons that people tend to look at Varget, I wanted to look at the primer question. I still have about 600 or 700 Remington 7 1/2 M primers that I was going to use in 308 as well, but a thought crept into my mind. If magnum primers provide more energy, does it make sense to be looking at using them to provide better ignition for cold soaked ammunition?
 
I've done a lot of hunting with reloaded ammo in the cold. I always use a magnum primer with ball powder loads as well as for extruded powder loads plus of 55 gr. Other than that, regular primers have worked just fine.
 
Magnum primers burn a bit hotter for a bit longer than standard primers. Cold weather(how cold is another thing) ignition is one of their primary purposes. Just remember that you'll have to work up the load again.
 
If it makes you happy to use magnum primers for cold weather hunting, then by all means use them. Personally, I would just use the standard primers you have.
Magnum primers were not even invented until some years after the 308 was on the civilian market. I'm sure many hunters hunted in cold countries with the 308, before there were magnum primers.
In the meat hunting years of the depression in the 1930s, the settlers in the cold, bush country of northern Canada, shot game year 'round, including in severe winter cold weather. The forests were also laced with year around trappers, who shot their rifles in the coldest of weather.
But all these men knew the secret of cold weather shooting. In the fall of the year they thoroughly cleaned the actions of their rifles in kerosene, then used them dry, with no lubrication of any type on vital firing pin areas of their rifles. And their rifles always shot and usually killed the animal they shot at, with the standard primers used in the factory loaded ammunition of the day.
 
I mainly ask because I accidentally picked up magnum primers a while ago. I don't have any normal LRPs kicking around, so I haven't built any loads to begin with. I am planning on loading Nosler Partition 180 grain spitzers, and the intent is to get them to push at about 2600 fps muzzle velocity, or close to it.

Regardless of how ammo had been loaded in the past, I'm pretty anal about my loads. Even my dad, former reservist, doesn't understand why I'm trying to weigh out my 500 S&W loads by metering, then balance beam, then trickle (or remove) powder so that the balance sits in exactly the same spot every time for every round. Since I keep hearing people talking about ignition issues in cold conditions, I was curious if my magnum primers would fare better for powder ignition than standard. When I run out, then I'll decide from there whether I stick with magnums or move to a good LRP.

I intend on testing how loads perform at 200m (and possibly up to 400m if I get the chance) in both cold and warm conditions. Essentially, I would like to put together the best round I can for my gun that can be used for hunting both short and long range predictably.
 
H4831 said:
If it makes you happy to use magnum primers for cold weather hunting, then by all means use them. Personally, I would just use the standard primers you have.
Magnum primers were not even invented until some years after the 308 was on the civilian market. I'm sure many hunters hunted in cold countries with the 308, before there were magnum primers.
In the meat hunting years of the depression in the 1930s, the settlers in the cold, bush country of northern Canada, shot game year 'round, including in severe winter cold weather. The forests were also laced with year around trappers, who shot their rifles in the coldest of weather.
But all these men knew the secret of cold weather shooting. In the fall of the year they thoroughly cleaned the actions of their rifles in kerosene, then used them dry, with no lubrication of any type on vital firing pin areas of their rifles. And their rifles always shot and usually killed the animal they shot at, with the standard primers used in the factory loaded ammunition of the day.
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Who is talking about hunting?

You know very well that cold weather changes your loads and the OP is simply looking for a way to avoid having to change his load for cold weather.

OP, I have read a lot about people doing this, but it all comes down to the accuracy level you are looking for. I tried it with some H335(very temp sensitive) and the magnum primers did not make up for the difference between the hot and cold weather.

I now have a bunch of Varget to load for my newest .223 rifle which will be shot all winter. ;)
 
Living in the north, logistics are simplified by choosing a single type of primer, so I just ignore the entire discussion and use magnum primers for everything except match ammo. When I lived down south, I'd use magnum primers for ball powder loads, when extruded loads exceeded 50 grs, or when the temperature dropped below 0F. In retrospect, just using magnum primers for everything, seems so much easier.
 
Boomer said:
Living in the north, logistics are simplified by choosing a single type of primer, so I just ignore the entire discussion and use magnum primers for everything except match ammo. When I lived down south, I'd use magnum primers for ball powder loads, when extruded loads exceeded 50 grs, or when the temperature dropped below 0F. In retrospect, just using magnum primers for everything, seems so much easier.
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Boomer, you are in an excellent area to do some hands on testing.
This winter, why don't you do some testing for us. Load exactly the same for two or three calibres, except in half use standard primers and in the other half use magnums. Treat them all exactly the same, having them out in the cold for some time before you shoot them over a chronograph, even alternating them shot for shot, as the rifles heat up.
I'm sure a lot of us would like to see the results.
 
All rifle primers loaded at Lake City Army Ammunition plant are magnum primers regardless if ball powder is used or not.

CCI No.34 and No.41 military rifle primers
Mil-spec sensitivity
Initiator mix optimized for ball/spherical propellants
Available in large (No.34) and small (No. 41) rifle
Use the same data as CCI Magnum primers

Look at the primer flash photos and read the test results at the bottom of the article.

Primers - Large Rifle Primer Study
A Match Primer Study in the 30-06 Cartridge
By Germán A. Salazar
This article was originally published in the September, 2008 issue of Precision Shooting
http://riflemansjournal.########.com/2009/06/primers-large-rifle-primer-study.html


Primers - Small Rifle Primer Study
A Match Primer Study in the 6BR Cartridge
By Germán A. Salazar
This article was originally published in the June, 2008 issue of Precision Shooting
http://riflemansjournal.########.com/2009/06/primers-small-rifle-primer-study.html
 
H4831 said:
Boomer, you are in an excellent area to do some hands on testing.
This winter, why don't you do some testing for us. Load exactly the same for two or three calibres, except in half use standard primers and in the other half use magnums. Treat them all exactly the same, having them out in the cold for some time before you shoot them over a chronograph, even alternating them shot for shot, as the rifles heat up.
I'm sure a lot of us would like to see the results.
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You know, that's not a bad idea.

Lets say 5 cartridges: .222 magnum, .270 .308, .375 Ultra, and .458 which should cover the normal span of cartridge powder capacity and velocity. I'll use ball powder in the .222 mag, .308 and the .458, and extruded in the .270 and and the .375 Ultra. I'll shoot 5 rounds with a standard primer, and another 5 with a magnum primer, then as a final test, I'll put a pinch of Bullseye between the magnum primer and the main powder charge of the .375 Ultra.

I'll do one test soon before it gets cold, and another once it drops into the low -30s. The tricky part in the extreme cold is to get reliable readings from a chronograph, but if I use my Chrony rather than the Oehler 35P, I only have a single wire to worry about, and I can keep the LED display in the warm truck while the instrument is set up outdoors. In the cold weather testing, the rifles and ammo would be left outdoors for several hours prior to firing. A drop in velocity is normal between warm and cold shooting conditions, and will be observed regardless of the primer used, what will be interesting is the round to round uniformity.

I'll choose brass which as closely as possible has the same volume for each cartridge, and weigh all the powder charges on the same scale. Typically I weigh thrown charges of ball powder on a balance beam scale and use a digital scale to dispense and weigh extruded powder charges. I seat primers with an RCBS bench mounted tool, primer pockets will be uniformed and flash-holes deburred and uniformed. For our test I'll use the balance beam scale for both, and balance the scale to weigh each specific charge using a check weight set, and load all the test ammo on the same day. In each case I'll use a "normal" bullet weight in each cartridge.

In blasting we learned early the difference between a good shot and a disaster is often related to adequate priming. The primer must not only produce sufficient energy to set off the explosive column, but it must be sufficient to maintain a steady state velocity of detonation (VOD) the entire length of the explosive column. I strongly suspect that this test will show that a similar relationship exists between primers and propellant powders in rifle cartridges. But I will do nothing the skew the test, and perhaps some others can conduct a similar test and notes can be compared, when I post my findings.
 
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I haven't seen a difference in different temperatures.

I have a bunch of old WLR's that I'm burning off in plinking loads because they are so hot in they don't work well in full power loads..

For faster powders I've been using cci200's with great success and consistency in 30-30 especially. They are a relatively 'cold' primer.

For my 270 and 7mm mag loads I've switched to federal 215's just to simplify things but as far as needing a 'hotter' primer when it's cold I think it's hokus pokus.

Google primer brisance and you will find plenty of tests guys have done and charts about how powerful different ones are. For instance, Winchester WLR's are hotter than some magnum primers. Does it make a difference in the cold? I don't think so.

I've found that matching the primer to the powder makes a difference in accuracy. They will all light off no matter what temp. I'd really like someone to chime in and say that they had a fail to fire because their primer wasn't hot enough but I bet no one will.

Like I said, matching the primer to powder for accuracy is more important than worrying if it will light off when it's cold out.

Just because some are labeled as a 'magnum primer' doesn't mean much. If they're accurate, use them. If not? Buy some different ones and save the ones you have for another load down the road. Primers are the cheapest reloading component.


just my $0.02
 
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In terms of accuracy, you can attempt to match the primer to the powder or the powder to the primer. At one time I used Winchester 120s pretty much exclusively, and these primers are formulated to provide reliable ignition for ball powders, and in my experience are hot enough for cartridges with .30/06 or even .300 Winchester capacities. Until fairly recently, Winchester didn't even market a magnum primer, but probably started due to public demand and due to the big capacity cases like the Ultramags, the various .378 Weatherby based cartridges, and the .338 Lapua, which have become popular in some circles.

When using standard primers at low temperatures, you might observe more unburnt powder particles being left in the bore, but I too doubt you would experience a failure to fire, provided your action wasn't gummed up. But as for the need of a hot primer in the cold, our test should tell the tale. If we ordinarily observe a 50 fps variation in velocity, but with standard primers at -38 observe a velocity variation of 200 fps, it might suggest a priming issue.
 
Boomer, I don't know if we're allowed to send primers through the mail but if so I'll send you a pack of my old WLR's to try. They're the old silver ones from the 80's. I'm curious what you'd think of them.
 
I don't know. I won't touch them anymore though.

I've read enough horror stories here and at 24hour camp about quality control issues that I steer clear of them now.

I don't want any holes in the bolt faces of my rifles.
 
07blackwater said:
---------- "I'd really like someone to chime in and say that they had a fail to fire because their primer wasn't hot enough but I bet no one will."------

There could be lots who could chime in and say this. Only the cause of their rifle likely not firing in cold weather would be a weak primer in about 1 % of the cases and a slow moving firing pin in about 99 % of the cases.
I grew up in the bush country of north easterly Saskatchewan, where winter temperatures would be on a par with where Boomer now lives. As a very eager teen ager, extremely interested in shooting and hunting, by the time the meat hunting era ended, I was vey familiar with men hunting and shooting game in severe winter weather, sometimes in the minus 45 degree range.
They had no control over the ammunition, including the primers, because they all just used Dominion factory ammunition, which would all be loaded with the same primers.
While the 30-30 class of cartridges dominated, there were some calibres used that had quite a large capacity for powder, such as a 43 Mauser, a 57 Snyder, one or two 30-06 rifles and the odd 303 British.
Every single one of those cold weather hunters knew they had to thoroughly clean their rifle actions of oil in the fall and leave them dry for winter. As a side note, to keep from having to clean and dry their rifle after bringing a super cold rifle into a warm log house, most of them, especially the trappers, never brought their rifles inside until spring! Walk up to many a homestead house or trappers cabin and if the man of the house was home, his rifle would be hanging outside in some covered area, like a little porch over the door, with a loaded magazine, likely one in the barrel and the hammer on safe.
As a scientific note to this bit about primer strength, there was a long article in some type of reloader book I had, but can't find now. It described a lab test on primers, measuring the amount of fire each primer emitted. They had the test rigged up to also measure the simulated hammer fall of the blow that set off the primer.
Bottom line was that the strength of the blow that set off the primer, had more to do with the fire power the primer gave off, than did the type of primer tested.
They plainly stated that a standard primer with a heavy firing pin blow gave off more power than did a magnum primer with a weak blow of the hammer.
Thus, if a cartridge failed to fire in cold weather, there would be far more chance the reason was a weak hammer fall because of an oily firing pin mechanism than a primer that failed in the cold.
On another side note, I read the results of another test of primers and in that test the primer that gave off the most fire power of any primer tested, was a standard primer of RWS brand.
I don't know if RWS primes are still available in Canada, but I have some left over from the 1960s and If it wasn't strictly against the law to mail primers, I would send some to Boomer, if he wanted them, for his very interesting up coming primer test.
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