While I have used magums in place of standards many times without any issues, I was just wondering what anyone else's experience is. My loads are at the low end of the scale and using magnums small pistol primers seem to work just fine. No signs over pressure. With the primer shortage around here, I have had to use what I can get. Anyone else ?
Magnum small pistol primers in place of standards ??
- Thread starter TINCUP AL
- Start date
Since the magnums burn hotter and increase pressures, you are smart to reduce your loads accordingly. I don't use them in place of, simply because I would have to to make adjustments to favorite loads to fix a temporary issue.
I've placed back-orders with suppliers last month and know eventually they will be filled.
I've placed back-orders with suppliers last month and know eventually they will be filled.
I have used them is 222 Remington and 22 K Hornets with no problems. I have a bunch of them(10,000) I got at an estate sale,Great place to find reloading components by the way. I have thought about using them in 223 contender I have but have not gotten around to it yet. So yes I have substituted SP Mag Primers for SR primers before. I would not do it in a AR style gun though, all of these are either Bolt guns or Single Shot. I did not see a big difference in Velocity versus SR Primers. Nor did I notice there was unburned powder in the barrel or case. No signs of pressure.
If you want to substitute them for regular SP primers in say a 38 SPL I would go ahead and do it. I might drop the powder down a little if you are loading near max or shooting them is a weaker style gun like a J frame S&W. But other than that I would use them.
I have no empirical evidence of this but I don't think MAGNUM primers have all that much more power. I think it is more heat and duration of ignition. I have seen studies in Gun Magazines that say there is not all that much difference. In fact I use Winchester WLP primers in all my LG Primer Pistols because it preforms well in either Magnums or Standard cartridges. The only time I reach for the "True" Magnum LP Primers is when I am using heaping amounts of W296 or H110 and the old WLP's do fine with W296 but not so hot with H110.
If you want to substitute them for regular SP primers in say a 38 SPL I would go ahead and do it. I might drop the powder down a little if you are loading near max or shooting them is a weaker style gun like a J frame S&W. But other than that I would use them.
I have no empirical evidence of this but I don't think MAGNUM primers have all that much more power. I think it is more heat and duration of ignition. I have seen studies in Gun Magazines that say there is not all that much difference. In fact I use Winchester WLP primers in all my LG Primer Pistols because it preforms well in either Magnums or Standard cartridges. The only time I reach for the "True" Magnum LP Primers is when I am using heaping amounts of W296 or H110 and the old WLP's do fine with W296 but not so hot with H110.
TINCUP AL -
My experience with pistol primers and light loads tracks with yours.
Most of what I load is lite target ammo for my pistols, so I use about any primers and don't worry about pressure --- but I still shoot a couple of groups any time I change a component just to be sure of the accuracy.
But then again, I just started reloading in the 1960's so what do I know....
...and over the years, I have read about folks that found the best accuracy in their particular gun with mag primers, depending on the cartridge, bullet, powder, etc. etc.
When I was doing a lot of load testing with my chronograph, I accidentally found one lot of regular CCI small rifle primers that was way more consistent than any other brand or lot I had ever seen.
Naturally, I went all over town and purchased every box of that lot number I could find.
My experience with pistol primers and light loads tracks with yours.
Most of what I load is lite target ammo for my pistols, so I use about any primers and don't worry about pressure --- but I still shoot a couple of groups any time I change a component just to be sure of the accuracy.
But then again, I just started reloading in the 1960's so what do I know....
...and over the years, I have read about folks that found the best accuracy in their particular gun with mag primers, depending on the cartridge, bullet, powder, etc. etc.
When I was doing a lot of load testing with my chronograph, I accidentally found one lot of regular CCI small rifle primers that was way more consistent than any other brand or lot I had ever seen.
Naturally, I went all over town and purchased every box of that lot number I could find.
James R. Burke
New member
I know thinks are getting really hard to get. But I have been able to find what I need at some of the smaller ma and pa type shops, so I have not had to change anything yet, and dont plan to. Just dont feel like starting over with something differnt when I already have it worked out. You would need to start from the min again, and work up. But always do what the manual calls for. Keep it safe! The supplys will come back as soon as people get what they feel they need or run out of money doing it.
caught
I use Magnum primers in numerous 'standard' loads, except with this caution:
WARNING, Winchester Small Pistol Magnum primers differ significantly from all other brand Small Pistol Magnun primers, and should NOT be used unless SPECIFIED in the data.
They are known to potentially increase pressure by as much as 5,000 PSI.
I use Magnum primers in numerous 'standard' loads, except with this caution:
WARNING, Winchester Small Pistol Magnum primers differ significantly from all other brand Small Pistol Magnun primers, and should NOT be used unless SPECIFIED in the data.
They are known to potentially increase pressure by as much as 5,000 PSI.
FWIW, I've used Winchester sm. pistol mag primers with Blue Dot, Red Dot & Unique in moderate .357 mag / 158 gr. JHP loads for many years with no signs of over pressure ( cratered primers, sticky extraction, etc. ) . Again, my loads are moderate ( mid to mid upper ) . Blue Dot loads were 2 full grains under Sierra's max. Red Dot loads were 1/2 grain under Hornady max. My current Unique load is 8 tenths under Lyman #47 max. Obviously, your mileage may vary if using them in max loads and / or max loads with different powders. One always needs to work up & watch for red flags .
I've been using magnum pistol primers in place of standard primers since I started reloading. Never had an indication of over-pressure.
To be honest, maybe I'm just lucky. The reason I started off with and stayed with magnum primers is because all my loading is done in .357 "Magnum" ("magnum", get it?), so I just assumed from the get-go that I should be using "magnum" primers.
At the same time, I have never loaded more than minimum loads. The singular reason I started reloading is because I wanted to lighten up the recoil of my .357 handguns and make them more fun at the range while avoiding using the shorter .38 brass.
I still have several boxes of magnum primers left and unless compelled otherwise, will continue to use them up in the (light) loads I've been using all along.
To be honest, maybe I'm just lucky. The reason I started off with and stayed with magnum primers is because all my loading is done in .357 "Magnum" ("magnum", get it?), so I just assumed from the get-go that I should be using "magnum" primers.
At the same time, I have never loaded more than minimum loads. The singular reason I started reloading is because I wanted to lighten up the recoil of my .357 handguns and make them more fun at the range while avoiding using the shorter .38 brass.
I still have several boxes of magnum primers left and unless compelled otherwise, will continue to use them up in the (light) loads I've been using all along.
The documentation that comes with the QuickLOAD internal ballistics program makes the interesting observation that what constitutes a magnum primer is not consistent industry-wide. Some just use more priming mix, making them hotter, while some some adjust the mix to increase flame duration and are actually milder at initial firing. This means that with a fast powder, the latter type might actually give you lower peak pressure. Unless you know your specific brand's approach to making a magnum primer, you need to assume it will raise pressure, but it isn't necessarily so, depending on what all else is in the mix. Since QL is written in Europe, I assume that description includes European brands and don't know how much of it applies to U.S. domestic brands?
In general, primer consistency is what matters most. Benchrest rifle shooters swear that having the mildest possible primer is best for accuracy, since that lets the powder charge control the peak pressure better, and the shooter is in control of the powder charge. However, that assumes relatively warm loads, good case fill, and completely prepped brass. I found, for example, that shooting Accurate 2520 in .308 I got a significant accuracy increase from using either magnum primers or by using Federal 210M (benchrest) primers but first deburring the flashhole on the inside. This was all because ball powders are harder to ignite, and that was complicated by me using a load that did not fill the case all that well.
So, bottom line for handguns, I think, is that you won't see any accuracy difference in primers except maybe in the Contender and Encore or other single-shot pistols capable of rifle-levels of precision. It seems to be the kind of difference you may see only in guns shooting under an MOA. That is exceptional for most handguns. As I said before, you do need to assume changing to a magnum primer will raise pressure until proven otherwise, so work your loads back up from 10% low, same as you would changing any other component in your load.
In general, primer consistency is what matters most. Benchrest rifle shooters swear that having the mildest possible primer is best for accuracy, since that lets the powder charge control the peak pressure better, and the shooter is in control of the powder charge. However, that assumes relatively warm loads, good case fill, and completely prepped brass. I found, for example, that shooting Accurate 2520 in .308 I got a significant accuracy increase from using either magnum primers or by using Federal 210M (benchrest) primers but first deburring the flashhole on the inside. This was all because ball powders are harder to ignite, and that was complicated by me using a load that did not fill the case all that well.
So, bottom line for handguns, I think, is that you won't see any accuracy difference in primers except maybe in the Contender and Encore or other single-shot pistols capable of rifle-levels of precision. It seems to be the kind of difference you may see only in guns shooting under an MOA. That is exceptional for most handguns. As I said before, you do need to assume changing to a magnum primer will raise pressure until proven otherwise, so work your loads back up from 10% low, same as you would changing any other component in your load.
For what it’s worth, I use more non magnum primers in my .357 than anything else, and I have never had any issues with a standard primer working any less efficiently than a standard primer with most of the powders I typically use, even some ball powders. In comparisons through a chronograph I have never seen any really dramatic difference in velocities either, but it‘s always wise to work up a load when changing any component.
I have noticed a definite difference in accuracy when using a magnum primer versus a standard, so you might want to do a little experimentation there. Two particular loadings of mine that use 2400 and VV N110 give far better accuracy when using a standard primer versus a magnum, so you never really know what effect that may have in your handgun either.
I have noticed a definite difference in accuracy when using a magnum primer versus a standard, so you might want to do a little experimentation there. Two particular loadings of mine that use 2400 and VV N110 give far better accuracy when using a standard primer versus a magnum, so you never really know what effect that may have in your handgun either.
vonnieglen
New member
The only primers I could find last month locally were Federal small pistol magnum primers. With great trepidation I substituted them in my Nagant Revolver, Makarov 9x18, and Tokarev cartridges using Titegroup powder and starting light. I did find some Titegroup recipes ahead of time which used magnum primers. Titegroup leaves these cases just half to a third full to begin with, but is designed to be used that way.
With Titegroup powder the magnum primers made very little difference and the loads were consistent according to my chronograph. I never saw any over-pressure signs. I used up the box of a thousand and am now back to the CCI small pistol primers that I normally use. I don't have the experience level of most here, but I think the powder selection could be very important with primer substitution. Titegroup is a fast powder.
With Titegroup powder the magnum primers made very little difference and the loads were consistent according to my chronograph. I never saw any over-pressure signs. I used up the box of a thousand and am now back to the CCI small pistol primers that I normally use. I don't have the experience level of most here, but I think the powder selection could be very important with primer substitution. Titegroup is a fast powder.
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Magnum small pistol or standard
Quote from Hornday 7th edition on the subject of primers:
"Magnum primer ..... produce more useful in burn large volumes of powder in the Cartridge." "Under no circumstance should one switch to a magnum primer with a load developed with a standard primer."
So it looks like if you don't have a large cartridge like those in Magnum guns,
You should not be using magnum primers. I am starting to reload. And will be doing 9mm lugers, So i defiantly can not use magnum primer because the Cartridge is rather short and does not have a whole lot of powder to burn.
Quote from Hornday 7th edition on the subject of primers:
"Magnum primer ..... produce more useful in burn large volumes of powder in the Cartridge." "Under no circumstance should one switch to a magnum primer with a load developed with a standard primer."
So it looks like if you don't have a large cartridge like those in Magnum guns,
You should not be using magnum primers. I am starting to reload. And will be doing 9mm lugers, So i defiantly can not use magnum primer because the Cartridge is rather short and does not have a whole lot of powder to burn.
Yup. All you have to do is knock the load developed with the standard primer down about 5% and work it back up, watching for pressure signs. All military primers are magnum primers, even though .45 ACP, 9 mm, 5.56 NATO, 7.62 NATO and other military rounds are not magnum ammunition. The reason is they have extreme low temperature ignition reliability requirements that standard primers don't meet. So they use magnum priming mixes and just work the loads up together with them.
Y`all watch this !!!!!
I took a #2 pencil & a 6" 357 & shot it into the air, not much difference until I got to the srp primers!!! 1 srp demolished the pencil !!!
I had too much time that day !!!
But still safe & sane practices should be followed especially all the time !!!
I took a #2 pencil & a 6" 357 & shot it into the air, not much difference until I got to the srp primers!!! 1 srp demolished the pencil !!!
I had too much time that day !!!
But still safe & sane practices should be followed especially all the time !!!