is it safe to load magmum primers in non magnum loads? i would load 5.8 grains of unique with 115 gr. plated rainer bullets. using winchester mag. primers. is this safe? i would appreciate all comments on this subject. thanks scooter-2
magnum primers?
- Thread starter scooter-2
- Start date
Register to hide this ad
My largest concern with magnum primers in handguns (especially older handguns) is that the hammer strike may not be strong enough to fire a magnum primer.
James Calhoon reports: "small pistol primers are .017" thick and large pistol primers are .020" thick."
Primers And Pressure
I'm not sure whether magnum and standard small pistol primers are the same thickness. Seems to me that if they were, Mr. Calhoon would have reported it.
I guess we can assume that magnum pistol primers are "brighter." Whatever that means. I have yet to see any chronograph data that would support a conclusion that magnum primers generate higher pressures.
I changed from standard rifle primers to magnum rifle primers in my AR-15 handloads. Chronograph data did not change. The problem with pierced primers did go away though when I switched to the magnum primers. (Cup thickness of small rifle primers DOES vary between standard and magnum versions - see the Calhoon article cited above.)
James Calhoon reports: "small pistol primers are .017" thick and large pistol primers are .020" thick."
Primers And Pressure
I'm not sure whether magnum and standard small pistol primers are the same thickness. Seems to me that if they were, Mr. Calhoon would have reported it.
I guess we can assume that magnum pistol primers are "brighter." Whatever that means. I have yet to see any chronograph data that would support a conclusion that magnum primers generate higher pressures.
I changed from standard rifle primers to magnum rifle primers in my AR-15 handloads. Chronograph data did not change. The problem with pierced primers did go away though when I switched to the magnum primers. (Cup thickness of small rifle primers DOES vary between standard and magnum versions - see the Calhoon article cited above.)
Hook686
US Veteran
I use magnum primers in ,357 magnum and .44 magnum with Unique and 2400. I figure it is about equivilent to .1, or .2 grains of powder I do not load close to, or at, the maximum loads shown in any of my reloading manuals.
ArchAngelCD
Moderator, SWCA Member, Absent Comrade
If your load isn't up near the top end of the pressure range go ahead and use the magnum primers without a change in your load. If you're bumping right up against the pressure limits you might want to drop back a hair just to be safe.
For the most part there is very little difference between a standard and magnum primer. A magnum primer will burn slightly hotter and slightly longer than a standard primer but that's is. Just because a caliber has the word magnum in it doesn't necessarily mean you should use a magnum primer. It's the powder you use that will dictate if you need a magnum primer or not. Hard to ignite Ball Powders like W296/H110 HS-6 and HS-7 require a magnum primer. Powders like 2400 don't need a magnum primer even when being used in magnum calibers because 2400 isn't hard to ignite.
IMO this topic needs a tutorial sticky...
For the most part there is very little difference between a standard and magnum primer. A magnum primer will burn slightly hotter and slightly longer than a standard primer but that's is. Just because a caliber has the word magnum in it doesn't necessarily mean you should use a magnum primer. It's the powder you use that will dictate if you need a magnum primer or not. Hard to ignite Ball Powders like W296/H110 HS-6 and HS-7 require a magnum primer. Powders like 2400 don't need a magnum primer even when being used in magnum calibers because 2400 isn't hard to ignite.
IMO this topic needs a tutorial sticky...
ArchAngel is this true even though my Lyman manual specifies use of magnum primers with 2400 in .357 loads? I'm all for saving a buck where I can ...
Dragon88
Member
How old is your Lyman manual? Alliant put the word out years ago, standard primers only for 2400.
Pisgah
Member
With rare exceptions, I use only standard primers even in magnum loads. The main reason is that once upon a time I did some pretty extensive chronographing of loads using magnum and standard primers and found that the main difference was that standard primers gave me much more consistent velocities and better accuracy. With 2400 and other slow powders, velocities tended to be higher with magnum primers but, again, more inconsistent, and I found that applying a heavier crimp gave me better consistency and almost equal velocities with standard primers. Particularly with 2400, I found that the heavier crimp also greatly reduced the amount of unburned powder -- one positive result many often claim for the magnum primers.
ArchAngelCD
Moderator, SWCA Member, Absent Comrade
Yes, it's completely true.ArchAngel is this true even though my Lyman manual specifies use of magnum primers with 2400 in .357 loads? I'm all for saving a buck where I can ...
It seems the current crop of manuals are not picking and choosing the primers as they should. They are using a standard primer in "non-magnum" calibers and magnum primers with anything the the magnum name. I'm guessing they are doing so to make things easy on themselves for testing.
If you look in almost any current manual for example you will see HS-6 when used in the .38 special listed with a standard primer and when used in a .357 Magnum they use a Magnum primer. That holds true with 2400 too as you mentioned. Unfortunately the writers aren't doing the same job that was done by their predecessors.
Alk8944
US Veteran
ArchAngelCD
Moderator, SWCA Member, Absent Comrade
There are powders which really shine when a magnum primer is used like W296/H110 and HS-6 or HS-7.
Magnum primers are great, for the purposes they are made for:
Very large cases of very slow powders.
Some ball powders, especially WW 296 and H110.
Other loads where a hotter flame and longer burn time are required.
Some "experts" claim they raise pressures, some "experts" claim they lower pressures and other "experts" say they do neither. They all have proof to back their claims and theories to explain them, so what do you do?
Anytime you use published data start low and work your way up because their equipment will not be the same as yours.
Anytime you work up a load and change any component from the original load, start low and work your way back up to a safe level for that load.
There are many things that can change pressures, and not just primers, so if you want to talk safety, this is where you start.
All brands of primers are different, even between the same types. Changing between a certain small pistol primer to another can raise, or lower, your pressures and velocities. But most of all they can have an even wider effect of accuracy, if that is of any concern.
If you're just out to make noise, choose your primer, start at a safe beginning load and work up to where you want. If you want accuracy, you might want to look at several different primers to see which performs best as you work up loads with each different primer. That is the joy of reloading, you have a reason to shoot a lot more.
Very large cases of very slow powders.
Some ball powders, especially WW 296 and H110.
Other loads where a hotter flame and longer burn time are required.
Some "experts" claim they raise pressures, some "experts" claim they lower pressures and other "experts" say they do neither. They all have proof to back their claims and theories to explain them, so what do you do?
Anytime you use published data start low and work your way up because their equipment will not be the same as yours.
Anytime you work up a load and change any component from the original load, start low and work your way back up to a safe level for that load.
There are many things that can change pressures, and not just primers, so if you want to talk safety, this is where you start.
All brands of primers are different, even between the same types. Changing between a certain small pistol primer to another can raise, or lower, your pressures and velocities. But most of all they can have an even wider effect of accuracy, if that is of any concern.
If you're just out to make noise, choose your primer, start at a safe beginning load and work up to where you want. If you want accuracy, you might want to look at several different primers to see which performs best as you work up loads with each different primer. That is the joy of reloading, you have a reason to shoot a lot more.
Hook686
US Veteran
Interesting that a few years ago the Alliant web site showed magnum primers for their .357 magnum loads. I emailed Alliant and asked why the magnum primer use and the reply was something like, ' Those were just what we had on the bench that day."
I remember learning that a standard small pistol primer is rated to around 30,000 psi chamber pressure. A magnum small pistol primer is rated higher in the 40K's.
Maybe things have changed and they all have the same cup thickness now.
amazingflapjack
US Veteran
I have used Winchester Large Pistol Primers in 44mag-45acp or any other case that calls for a large primer, for a yeaar or so now. They are rated for both standard and magnum rounds, and I like the results. The powder seems to burn cleaner. I use Unique in these cases, and allow for them, not going to max loads. It has worked well for me. Flapjack.
jimslim
US Veteran
i use winchester primers for 19 gr 2400 for 44 mag ,8 gr unique for 45 colt . accurracy seems to be consistent for both loads but i get a lot of flash on the top strap around the forcing cone . curious as to wether this build-up of heavy flash is cosmetic or something that occures from the use of winchester WLP primers .
Last edited:
During the last primer shortage I used mag primers when I couldn't find what I needed.All the loads I used them with were mid range charges.
This came up last year IIRC. At that time, Remington was still recommending the use of their 5 1/2 magnum small pistol primer with .40 S&W and .357 magnum primers. Possibly also for the 357 Sig, all due to pressure concerns.
I've never bothered with magnum small pistol primers. I did once use magnum primers with some .44 magnum unique loads and noted increased leading. Since then, I've restricted my use of magnum pistol primers to lighting IMR 4227 in .44 Magnum loads.
I started using up some Magnum LP primers in 44wcf loads recently (Winchester 73).
They give a bit better accuracy than the standards. Shooting a cowboy load of Red Dot and 200gr FNL.
Great accuracy in the 1889mfg rifle. It's a rebore (done by Ken Bresien) from 38wcf to 44wcf.
I'll use 'em up there and in light 44Spl loads in an OpenTop repro where they also give great accuracy with 245grLSWC.
,,I seem to have a couple bricks of mag primers.
Perhaps those fairly light loads in large cases gets better consumed/burned by the mag primer.
They give a bit better accuracy than the standards. Shooting a cowboy load of Red Dot and 200gr FNL.
Great accuracy in the 1889mfg rifle. It's a rebore (done by Ken Bresien) from 38wcf to 44wcf.
I'll use 'em up there and in light 44Spl loads in an OpenTop repro where they also give great accuracy with 245grLSWC.
,,I seem to have a couple bricks of mag primers.
Perhaps those fairly light loads in large cases gets better consumed/burned by the mag primer.
trauma1
Member
Wow. It is amazing this debate is still going. First, magnum primers are generally"thicker" than standard primers - meaning a thicker amount of metal at the firing pin. The exception would be Winchester primers which I have used for both very light 38spl target rounds to super heavy 45colt rounds(300gr cast bullets). One person commented about velocity and pressure signs. In truth, by the time any pressure signs show up in a modern gun the pressures are way beyond SAAMI max limits. The best rule is to stick with the the recipe that was formulated by the powder/bullet/gun company to begin with. If it says to use a standard primer then use it. One is not going to gain any extra velocity from using a magnum primer. Likewise, if it says to use a CCI magnum primer then use it. There is not alot of price difference between the two and a bad load is much better than a blown up gun. I have witnessed a 2nd generation colt blown in half due to a faulty load. OUCH! Stick to the recipes!
Similar threads
- Locked
