Magnum Primers
- Thread starter tilo
- Start date
blaser.306
CGN Regular
- Location
- Saskatoon , Sask
Some claim it to be neede if you are loading with "ball" type powders as they can be harder to lite espcialy in cold weather ? Myself I have not seen it as a problem but YMMV.
I only use magnums in all my 223. I developed the load from the starting point and never tried normal primers so I'm not sure.
I recently switched to magnum primers in all my 45-70 loads and there is zero difference in muzzle velocity for either full power jacketed or reduced power cast bullets.
Safest bet is to work up a new load from starting values if you change primers. Even changing brand of primer I would do this as different brands have significantly different amounts of flame.
I recently switched to magnum primers in all my 45-70 loads and there is zero difference in muzzle velocity for either full power jacketed or reduced power cast bullets.
Safest bet is to work up a new load from starting values if you change primers. Even changing brand of primer I would do this as different brands have significantly different amounts of flame.
I "ALWAYS" start low and work up and most manuals tell you to reduce by 10% and work up even when changing primers. This rule holds very true when your loads are near maximum so be safe and work up.
In all my reloading manuals from the early 1970s list magnum primers with all ball powders and large loads of slow burning powders, these were marked by a * by the individual loads. In later to present day manuals you no longer see the asterisk and under components used you will see primer recommendations.
In just looking I see some of the newer manuals will say "magnum or standard" primers" for a given caliber and load. Also with workup start loads at the lower pressure end and if snow is on the ground you can sometimes see unburned powder laying on top of the snow. Meaning some powders burn better at higher pressures and a magnum primer can start the pressure curve earlier and get the ball rolling sooner.
The military still uses magnum primers with all ball powder loads, I use magnum primers in my AR15s with ball powders. I also used a magnum primer in my short barreled Winchester 30-30 Trapper model with a 16 inch barrel when using 748 powder.
In over 45 years of reloading the biggest difference I have seen between magnum and standard primers is with rifles with shorter barrels using ball powders or slower stick powders. Also remember in your car the proper heat range "spark plug" is very important and the same holds true of primers.
Today as an example the Sierra manual lists a standard Remington 7 1/2 primer with all loads listed and even ball powders with the AR15 using the HBAR target rifle below.
CHOOSING THE RIGHT PRIMER - A PRIMER ON PRIMERS
http://www.sksboards.com/smf/index.php?topic=56422.0
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- Location
- Somewhere on the Hudson Bay Coast
When I lived down south, my rule of thumb was to switch to a magnum primer when:
- the powder charge exceeded 50 grs,
- when the temperature dropped below 0 F,
- when I loaded ball powder.
Today I just use magnum primer's for everything except match ammo. The theory is that the best accuracy is realized with the minimum amount of primer violence that will reliably ignite the powder charge. Due to the difficulty and cost associated with shipping primers, powder, or factory ammo, when I buy, I tend to buy large quantities; my last Large Rifle primer purchase was 20,000. Once I have a recipe worked out, I'll load a year's supply or more at a single sitting, so not knowing when the ammo will be shot or what the temperature will be when I shoot it, choosing magnum primers is prudent. Additionally, I seem to be using more ball powder these days then I used to, H-110 in my revolvers, and H-335 and H-414 in my rifle cartridges, where before I might use W-296 in my revolvers, W-748 in my .222, and extruded for everything else.
- the powder charge exceeded 50 grs,
- when the temperature dropped below 0 F,
- when I loaded ball powder.
Today I just use magnum primer's for everything except match ammo. The theory is that the best accuracy is realized with the minimum amount of primer violence that will reliably ignite the powder charge. Due to the difficulty and cost associated with shipping primers, powder, or factory ammo, when I buy, I tend to buy large quantities; my last Large Rifle primer purchase was 20,000. Once I have a recipe worked out, I'll load a year's supply or more at a single sitting, so not knowing when the ammo will be shot or what the temperature will be when I shoot it, choosing magnum primers is prudent. Additionally, I seem to be using more ball powder these days then I used to, H-110 in my revolvers, and H-335 and H-414 in my rifle cartridges, where before I might use W-296 in my revolvers, W-748 in my .222, and extruded for everything else.
I am actually doing an experiment on primers. I have some 45 ACP with large and small primer pockets. I have loaded them with the same bullet, powder charge and brand of powder. I have also loaded some with magumun primers. The weather has to get above -10 so I can try it out and see the difference size and type of primer effects velocity.
I have seen a pic sequence of all the primers being fired off, and there is a very noticeable flame size increase in the magnum primer. I forget what site it was on but it stated how much more the pressure would increase and suggested that you drop your load by 1 grain and then test for pressure signs. The only place I thnik the magnum primer would really come into play is if you are running a super hot load and also maybe combined with hotter weather, thus raising the pressures to unsafe levels. Like most people say, drop your load and bring it up again.
paperslayer
Regular
- Location
- Chilliwack
I use nothing but CCI450s in anything with a small primer.
I use magnum primers with everything. I use the standard loads from the manuals but still use magnum primers.
For one thing, they seem to be generally more consistent and I don't have to worry about temperature flucuations with the older powders I have on hand.
Some people I know use Bench Rest primers instead because they fall in the middle area between magnum and standard.
I think there is way to much hype about standard and magnum primers.
I want my cartridge to go bang as consistently as possible under all conditions. I don't like to complicate matters any more than necessary.
When I was younger, I took a lot of time to check out different loads with different cartridges, over a chronograph to check load deviations under differing circumstances.
There was very little, if any velocity difference between that standard and magnum primers during good weather conditions. When it got very cold, minus 20C and lower, standard primer ignition left a bit to be desired. Under the same conditions, magnum primers kept things the same as less inclement weather.
I won't say the loads using magnum primers are more accurate, that really depends on the shooter and rifle. I will say velocities are more consistent and that is one of the basic principals of good accuracy.
