MAGNUM primers question.

Janeau said:
Were did you see that ? Post reference to your statement.
The 41 and 34 have a harder cup for use in semi auto to reduce the chance of slam fire.
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CCI has told me the same through email years ago. The Rem 7.5, which you can see is extremely energetic, was developed for the M193 load back in the '60s.
 
B said:
CCI has told me the same through email years ago. The Rem 7.5, which you can see is extremely energetic, was developed for the M193 load back in the '60s.
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Is what I was thinking..you cannot back it up because they are standard primer. Load data show those two can be used in replacement of their standard primer when used in semi.

I chrono a year back - both primer 41/31 for my AR15 , AR10 and Match M1A with my Labradar and and showed to same velocities range but with more variation than standard . They are not even close to low SD Benchrest primers provide All CCI.
The 41/34 are mill specs..that mean lousy specs and data showed that. Even standard CCI are better - than those two.
 
Janeau said:
You should look into the powder you use..if the primer goes bang..the problem is elsewhere.
It seem you have more problems with your reload that I got in 50 years of reloading, and I shoot close to 15K. every year - all seasons in outside range pistol - rifle. I do my hunting load. Have not purchased factory ammo -other than rimfire - since I started reloading..and I can count in one hand the time a round did not fire.
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There is a difference between 1 year of reloading repeated 50 times vs 50 years of continuous experimentation, and recording the results for educational purposes.

Science requires that results are repeatable.

I have found, a number of times, in various calibers, that a standard primer under ball powder with a light bullet causes problems.

I have shared that here.

If you want to claim I misunderstood what I did or saw, so be it.

The fact that you have not had a problem may just mean that you did not use a light bullet, or that you use more neck tension, or you used a hotter primer than I did.

The problem with ignition is that if it goes bang you can't tell how close it was to not going bang. If the ES is big, that is a good clue you are on the edge. A cold day could put you over the edge.

You wrote:
"You should look into the powder you use..if the primer goes bang..the problem is elsewhere."

Yes, the problem is the powder. It is too hard to ignite in that configuration - ball powder, light charge, light bullet, no crimp.

I once made a few thousand 223 rounds with ball powder and a 55 gr bullet. It was CQB (short range) so I only used 22 gr. I was getting 20% no bangs, with the bullet stuck in the throat.

I was not keen on pulling a couple thousand rounds, so I ran them through a Lee Factory Crimp die. That solved the problem.

In the future I loaded with a magnum primer and used a firm crimp.
 
What I was saying ..the problem was elsewhere. What powder were you using ? As you found out - proper neck tension is a must - but I personally shot thousand and thousand of .223 in my AR using a standard sizing die giving about .003 neck tension - never had to crimp.
One cartridge that does not need a magnum primer it is the small case such as the .223 ...

A magnum primer in a load that do not call for it — can rob you of better velocity and accuracy. It raise pressure for no gain. Using a standard primer might get you a few grains more of powder - low SD and better accuracy.

Have you heard of load density ? Going too light with some powder create ignition problems and wide velocity variation and poor accuracy - but shooting at close range in a CQB match might not have been a factor - accuracy speaking. But as you found out..ignition was another matter. Crimping hard with the Lee is a temporary fix..I would look into your choice of powder and the charge you are loading.

If you are happy with mag primer - go for it, but it’s definitely not needed with powder recommended for that round.
 
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Have we all turned into Americans here on Gunnutz???

Yet another thread that has gone downhill for no reason. Adversarial, pointless criticism, butthurt, it's just become so unpleasant.

I'll assume it's all a symptom of Covid stress but gee whiz, reloading has always been a pleasant Zen-like experience for me. So has learning about it.

40 years ago I learned from a few books and a half dozen guys I knew at the range. Now I can learn from thousands of people with different experiences and knowledge and instead it ends up like a cat fight between teenage girls in some high school jealousy drama.
 
Both the CCI 41 and 34 are magnum primers that have shorter anvils to make them less sensitive, read the links below.


CHOOSING THE RIGHT PRIMER - A PRIMER ON PRIMERS
http://www.sksboards.com/smf/index.php?topic=56422.0

Small Rifle Magnum

CCI 450 - same thicker .025" cup as the BR4 and #41.
CCI #41 - commercial version of the fully-qualified DOD primer for use in U.S. military ammo. With this primer there is more 'distance' between the tip of the anvil and the bottom of the cup than with other CCI SR primers. .025" thick cup. Same primer mix as CCI 450.

small rifle magnum primers ?
https://forum.accurateshooter.com/threads/small-rifle-magnum-primers.3982310/

The CCI #41 and CCI #34 are both magnum type primers One large difference between, for example a CCI #41 small rifle primer and a CCI 450 small rifle magnum primer is the CCI #41 also has the anvil at a slightly different angle in addition to the slightly thicker cup.

Question:
Regarding CCI #34 primers. The question has come up or it has been stated that CCI #34 primers are the same thing as CCI 250 Large Rifle Magnum primers. While I know the CCI #34 is a magnum primer I believe it is not the same as other large rifle magnum primers in that it has further reduced sensitivity. Would that be correct and is the priming mix different than standard large rifle magnum primers.

Answer:
Ron, here are the differences in the 2 primers. So the anvil angle change is the difference, this keeps the free floating firing pins from causing slam-fires in AR style platforms. This does make it so that a light strike will have a less of a change of going off.

CCI-250............................ Magnum primer, Mag primer mix, thick cup, standard anvil.
#34/7.62MM................... Mil. Spec. primer, thick cup, magnum primer charge, angle of anvil change.


Justin M./Technical Service Rep.
2299 Snake River Ave.
Lewiston, ID 83501
Alliant/Blazer/CCI/Speer
(800)379-1732

More from CCI, at one time the information below was at the CCI primer website.

From CCI:


Military-style semi-auto rifles seldom have firing pin retraction springs. If care is not used in assembling ammunition, a “slam-fire” can occur before the bolt locks. The military arsenals accomplish this using different techniques and components—including different primer sensitivity specifications—from their commercial counterparts. CCI makes rifle primers for commercial sale that matches military sensitivity specs that reduce the chance of a slam-fire when other factors go out of control*. If you’re reloading for a military semi-auto, look to CCI Military primers.
*Effective slam-fire prevention requires more than special primers. Headspace, chamber condition, firing pin shape and protrusion, bolt velocity, cartridge case condition, and other factors can affect slam-fire potential.


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
 
That's the same email I received as far as I remember, nicely done. It doesn't take any stretch of the imagination to think ammunition that is almost always loaded with ball powder would utilize a magnum primer. Because ball powders typically work better with them.
 
I have no proof, and have not experimented, but have been told that Magnum primers level out the performance of temperature sensitive powders; so I use them as a matter of course. This works well for me, so why change?
 
Meroh said:
I have no proof, and have not experimented, but have been told that Magnum primers level out the performance of temperature sensitive powders; so I use them as a matter of course. This works well for me, so why change?
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No primer change powder sensitivity, regarding temp. By sensitivity I mean burn characteristics that affect velocity and pressure.

If it was that simple..manufacturer will just have put magnum primer in every load, not change formulation and introduce the new powders along the line of Varget - who is well known to be a very stable temp powder - mean it reduce if not eliminate variations due to temp.
Powder temp sensitivity occurs once it is ignited if I can say that.

Why change ? If published load data - made by ballistic labs that know more than anybody - does not call for a mag primer - you are rising pressure in that load - possibly over the max pressure. You do not know - you experimenting blind. Small change peak pressure in a given load. Stick to published load data using the components stated, you will get better performance - safe reloads.

Load that use mag primer are developed by labs with specific powder and components for that load.

Look in manuals at powder used in magnum load - there is a small overlap - but mainly when you get into the 60 grains +- powder, it is a slower powder than smaller cartridge. Primer - powder - bullet match is necessary to stay safe and offer reliability and performance. This is why loads data exist in such large numbers - to match components together that work in a safe pressure range.

Another reason for not using magnum primer when not called for - is based on test done over the years in many publication - they do not offer the same low SD and velocity spread the regular primer does.

Some reading here. Other tests can change position - but in all reading done on this subject in the last 50 years , never put magnum primer as the best performer for low SD - BUT load using components developed with magnum primer can and do produce accurate load when used in load that call for it.

http://bulletin.accurateshooter.com/2017/04/ultimate-large-rifle-primer-shoot-out-16-types-tested/

I am amazed at how many reloader disregards load data and substitute components at will. This create all kinds of problems with loads and firearms.
 
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I have all the data I need to prove that my loads I have developed are simply better with magnum primers. I have plenty that utilize a standard primer but I load with magnums if possible and if my chronographing and accuracy testing show the results I want.

Saying the only way to load is out of a manual paints you as someone who clearly didn't learn anything at all in your supposed 50 years. Imagine how far back we'd still be without people doing their own experimation...

No one has advocated substituting primers without caution or due diligence. Saying you can't or shouldn't because a manual doesn't say to is just asinine though. Most get it but clearly some never will.
 
B said:
No one has advocated substituting primers without caution or due diligence. Saying you can't or shouldn't because a manual doesn't say to is just asinine though. Most get it but clearly some never will.
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I agree with you. Manuals or online data are not the only way - but it is the starting point.
Sometime data is very scarce or does not exist in some Wildcat or for a specific competition gun/load.
Ammo tailored for custom chambered gun are another example..nothing as per specs in manuals.

But here - it is impossible to know the level of the reloader experience - what he is reloading for. What you are doing or I am doing for the calibers we do reload is not a starting point. A newly graduated truck mechanic is not at the same place the guy doing it for 30 years +. One will follow the book or blindly what he is told, the other will use his experience and knowledge learned in those years.

For most if not the majority - they want to reload to save money - and make better ammo for their guns. There is other reasons but let say those are the mains that come along most of the time. The general advise to stick to know data is the right thing to promote in my book. It’s all there to reach those goals.
 
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I couldn't find the old email from CCI so I asked again shortly before biged posted his reply from them. I got an incredibly fast reply. Take note of the bolded part...

Me: Can you confirm that your milspec primers are formulated with a "magnum" priming compound?

CCI:

B,

These do have a hotter mix than the standard primers to more effectively light ball powders that many milspec rounds are loaded with.

Thanks,

Cody B./Technical Service Rep.

CCI/Speer/Alliant
2299 Snake River Ave.
Lewiston, ID 83501#
(866)286-7436
 
Heddok said:
Have we all turned into Americans here on Gunnutz???

Yet another thread that has gone downhill for no reason. Adversarial, pointless criticism, butthurt, it's just become so unpleasant.

I'll assume it's all a symptom of Covid stress but gee whiz, reloading has always been a pleasant Zen-like experience for me. So has learning about it.

40 years ago I learned from a few books and a half dozen guys I knew at the range. Now I can learn from thousands of people with different experiences and knowledge and instead it ends up like a cat fight between teenage girls in some high school jealousy drama.
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I don’t see it that way..but sorry If asking questions - providing infos come across that way.
Thats not the intend.
Asking were some infos come from is normal and if we do not agree does not mean a fight.:)
 
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B said:
I couldn't find the old email from CCI so I asked again shortly before biged posted his reply from them. I got an incredibly fast reply. Take note of the bolded part...

Me: Can you confirm that your milspec primers are formulated with a "magnum" priming compound?

CCI:

B,

These do have a hotter mix than the standard primers to more effectively light ball powders that many milspec rounds are loaded with.

Thanks,

Cody B./Technical Service Rep.

CCI/Speer/Alliant
2299 Snake River Ave.
Lewiston, ID 83501#
(866)286-7436
Click to expand...

Lol ! They do not want to say - write magnum..
Your question was clear...

There is no question those two are switch over for the regular primer for semi.
Marketing ?
I did not use those in any of my semis over the years and other manufacturer do not offer those. If they were a must do you think other manufacturer will not be onboard ?

Test your reload with them and regular - I found no benefit. The 450 does make a change.
As stated earlier by others posters - primer intensity vary by manufacturer.
The magnum designation of one Cie does not mean the regular of another brand is not equal or hotter.

Thanks for the infos. Great.
 
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Below is the original link for abbreviated posting at accurateshooter.com on large rifle primers. If you look at "Table 1 – Average MVs in ascending order" you will see the velocities and the CCI 250 magnum primer had a lower velocity and start pressure than the standard Remington 9 1/2 primer. The Remington 9 1/2 primers also had the smallest group size, look at the charts at the link below.

Also note Laurie tested 16 primers with the same load and the velocity only varied 35 fps. Meaning he deviated from published reloading data.

"BUT" the reloading manuals tell you any time you change reloading components to reduce the load 10% and work up again. And the chart below shows the standard Remington primer had the highest velocity and start pressure.


LARGE RIFLE PRIMER PERFORMANCE BY LAURIE HOLLAND
http://www.targetshooter.co.uk/?p=1471

Velocities

Primer choice affects MV, it’s as plain as that. The MVs recorded (Table 1) saw average values cover a 35 fps range, equivalent to a 0.7gn N140 charge variance. However, it’s not that straightforward. MV is a function of the total amount of pressure provided by the primer and propellant, the size of ‘the area under the graph’ (Fig. 2). Whilst the powder-burn accelerates the bullet throughout the barrel, albeit with reducing pressure after the first fraction of a millisecond of burn, pressure spikes very shortly after ignition and that’s what determines the maximum safe load. With the primer compound detonating, not burning like the main charge, it produces a ‘pressure-rush’ which enhances that initial peak, so the ‘oomph’ which produces an extra 35 fps at the muzzle will likely affect PMax disproportionately – the ‘wrong sort’ of pressure! I’ve graded results as ‘mild’ (2,780-90 fps); ‘warm’ (2,791-2,800 fps); ‘hot’ (>2,800 fps).



yPCct4r.jpg
 
Janeau said:
Lol ! They do not want to say - write magnum..
Your question was clear...
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Lake City uses magnum primers in all their ammunition even with single base powders. Below was from the CCI website, the only difference between the CCI 250 and the No.34 primers are the anvil height.

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
 
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