Magnum primers

[abunaitoo]

How much more powerful are magnum LR compared to normal LR?????.
Any problems using them in non-magnum cases?????
Have a bunch of them, but don't shoot anything that uses them.

[white eagle]

I have some as well and just used them in a 35 Whelen
I was using a flake powder and wanted to try them out
no problems no excessive pressure signs or nay related issues
you can substitute but start from the beginning don't just switch them out
with an existing load you have

[gumbo333]

In my time of reloading I've used lots of magnum primers. In cases like 223 (smallish) up to larger cases maybe 40 + grains using stick powder I would back off the powder charge 10% and work up. Using a ball powder under 40 grains I would likely use a regular loading manual recommendation. In larger cases with powder capacity over 40 or more grains of stick powder I would just use the magnum primer. In larger cases(40+ grains) of ball powder magnum primers are usually recommended. I seldom have found a need to load cases as hot as possible. I usually use what I have. Have had good luck with Federal mag primers better than CCI mag primers.

[blackthorn]

The only concern is if you are loading at or near maximum. As long as you are loading low to mid range, switching from LRP to LRMP will not be an issue, other than a slight difference in velocity and perhaps a bit of change in POI.

[TurnipEaterDown]

Magnum LR primers may or may not be "hotter" (i.e. generate more pressure, or shorten the pressure curve rise time to max) in a particular load, given some other non magnum comparative primer as the reference.
This is NOT a guess.

I ran a series of pressure tests w/ an Oehler M43 in a 475 Linebaugh Long years ago, and seeing how it uses a cut off 45-70 case, I used every large pistol and large rifle primer I could get a hold of.

I used the following primers as the single variable, with the remainder of the load being: WW 45-70 case cut to 1.600", 400gr LBT WFN (394 gr) 41.5 gr WC680 (lot 47271).
CCI 250 (Large Rifle Mag)
CCI 350 (Large Pistol Mag)
Federal 215 (Large Rifle Mag)
CCI BR2 (large rifle BR)
Winchester WLRM (L Rifle Mag)
CCI #34 (Large Rifle Military)
Winchester WLR (Large Rifle)
Federal 210 (Large Rifle)
Federal 150 (large Pistol)
Federal 155 (large Pistol Mag)
CCI 200 (Large Rifle)
CCI 300 (Large Pistol)
Winchester WLP (large pistol)

The difference in pressure from load producing the least peak pressure to greatest peak pressure was 8,100 PSI indicated.
A LR Magnum did top the list, but a LP did generate the second highest pressure.
Nominally this load did give me 1600 fps from a 10" barrel w/ brake. I had it in an Encore. Became tedious for me and taught me a flinch, so I sold it and spent the next 5-7 years "unlearning" my flinch w/ pistols.

I won't provide all the data, conclusions from one cartridge combination can be misleading to make guesses about loads in another.

As a useful load development trick when I have a cartridge that takes a large primer, has No Data or might have data but not for teh bullet I want, and I don't want high pressure, I will sometimes do load development w/ L Pistol primers. They handle 45-50K PSI fine (WLP & F155 always have in my 475 Linebaugh, 1.4"), and will yield and show defects on bolt face/recoil plate as imprints on teh primer cup sooner many times than a LR primer will.

[GregLaROCHE]

I bought 1000 because they were on sale once. I currently don’t have anything that calls for them, but have been using them in 45/70 BP loads, to save regular ones for other loads. I can’t say I see any difference.

[fayettefatts]

Magnum primers generally have a thicker cup. I use them in the 6mm br to reduce primer cratering. I have also found that my Rossi 92 with a reduced power hammer spring will not reliably fire them, while having no problem with standard primers. These are small rifle primers. Don't know about large.

[1006]

Wouldn’t they have to produce some additional heat? Otherwise, how would they be better suited to ignite certain powders?

Weather or not that extra heat translates into additional pressure with powders that do not require the extra heat is uncertain. At least I do not know for certain.

I generally use Magnum Primers with any of the Ball Powders, and in my AR.

[TurnipEaterDown]

Magnum primers (LR anyway) were developed to improve ignition in cartridges having larger charges of slower burning powder(s). True. If I remember correctly the F215 was developed specifically for the 378 Weatherby which had ignition issues w/ other LR primers available at the time.

However, how they do this is not necessarily related to Heat (i.e. Temperature).
One of the manuals or resource books I have (which I can not find to reference) speaks about different primer compositions & "Brisance" (spelling may be off). Some priming compounds use ground glass in the mix for instance, which when the primer ignites become small molten globules that transfer the primer effect deeper into the powder column inside the case.

The Norma Reloading Manual Volume 1 has a nice article about primers that is informative, and can help improve understanding of primer differences.

Contrary to many peoples writings and experience, I have had no negative experience w/ standard primers used w/ ball powders, even in colder weather (I will go out & shoot at range down to about 10°F now, used to go out in zero/sub zero in my twenties). I also have had no bad experience w/ std LR primers in cases burning 70 gr or so of powder (typically "magnum" territory). I will use a magnum primer in cases holding 80+grains, and will when using some very slow powders like the H870/AA8700/WC87x powders/5010. I will also use them when I have gross bore area to powder volume mismatch (65 gr in a 6mm bore, 90 gr in a 7 mm bore).

Note that there are also admonitions to NOT use magnum primers w/ some powders. My memory says that Hercules 2400 was one, and whether this still applies to Alliant 2400 I don't exactly know. This Can cause high pressure excursions is my understanding.

Best primer for the job might change w/ powder type, case volume to bore area, temperature conditions, pressure curve characteristics of cartridge combination, etc.

The suppliers do a nice job of providing robust designs that operate safely in a broad range of applications & conditions, but nothing is universal.

[NSB]

This question comes up frequently on this site and others. I follow the answers as closely as I can. From what I can gather over the years, it doesn’t seem to actually make much difference. That also goes along with the concept that there is no industry standard to designate what a magnum or non-magnum primer is. I have gotten to where I just buy primers labeled “magnum” most of the time (depending on supply and if I have a choice or not) and so far I have seen little if any difference in pressure indicators. I have found a few loads in certain guns over the years that simply group better with one brand of primer over another, and that’s not a mag vs non-mag cause, it’s just switching from brand to brand. I rarely shoot loads at the highest velocity, I look for most consistent/accuracy. My thoughts have always been to just work my way up and observe. Use what you have if that’s all you have.
Note: I do use magnum primers all the time with certain powders such as WW296/H110.

[Froogal]

I stumbled across a box of CCI large pistol magnum primers awhile back. Not really what I was looking for, but it was the ONLY box of primers at that particular gun show, so I bought it. I've used a few already, and honestly cannot see any difference between the magnum primers and the standard primers.

[Larry Gibson]

I've done a considerable amount of different primer pressure testing using the M43 Oehler PBL over the last 14 years. This testing was done with handgun cartridges and rifle cartridges. I've also done quite a bit of research on the composition of primers. I've learned a few things.

All primers, whether standard or magnum, are not created equally. Manufacturers change the composition of their primers more often than thought. They, most often, do not announce those changes. When comparing standard to magnum primers only those of the same manufacturer should be compared. Comparing a standard primer of one manufacturer to a magnum primer of another manufacturer is basically comparing apples to oranges.

Recent (probably the last 15 - 20 years) magnum primers have a different priming compound composition than the same manufacturer's standard primer. This is to give a longer flame burn time which of course increases the heat and pressure. How much....depends......

If you switch from a CCI LR to a CCI LRM there probably will be a pressure increase in a given load. How much.......depends.....

If you switch from a CCI LR to a Fed or Win LRM primer there probably will also be a pressure increase in a given load. Will it be more or less than with the CCI LRM.....depends.....

As you can see there are a lot of "depends" there. In case you haven't noticed in the loading and/or reloading of ammunition the results can and do vary because there are so many variables we can't control or aren't even aware of. That's why with many questions such as the OPs the answer isn't and can't be a hard and fast answer. Simply because it ......depends.

However, there are some things we can do to mitigate any potential pressure problems when switching from a standard primer to a magnum primer whether of the same manufacturer or not. If using a cast bullet load in a rifle cartridge the pressures are most often considerably less than the MAP for the cartridge. Thus, any increase in pressure the magnum primer may create is most often going to be within the safe parameters for the cartridge. The problem is your load may be at the "accuracy node" and the increase in pressure/velocity can decrease accuracy. Thus it is always best, when switching to a magnum primer to drop back 10% and work back up to the same level of velocity and accuracy.

If you are using a load with standard LR primers that is close or at the MAP, whether cast or jacketed bullets are used, then switching to a magnum LR primer probably would produce excessive pressure above the MAP for the cartridge. Again, with such it is best to reduce the powder charge and work back up observing for excess pressure signs.

A couple observations on several of the above posts. Most manufacturers for some time have been using the same primer cup material. Thus, there really isn't any "harder" or softer" primers made anymore. Also, magnum primer cups also are of the same and are not "harder" anymore. Those of us with caches of primers from years past may still find that different but primer cups made in the US the last 15-20+ years are the same whether standard or magnum. Foreign primers are another story.

I have been pressure testing standard and magnum LP primers in the 357 and 44 Magnum cartridges with 2400 (both Hercules and Alliant) and have yet to find any "pressure excursions". Sometimes, depending on the primer make used, there is no significant difference in the peak pressures but sometimes there is. But no real pressure excursions have been observed. I use WSP and WLP primers primarily with my 357 and 44 magnum 2400 loads. If those are not available, then I use a SPM or LPM of another make. Pressure have been consistent with either primer used.

[OutHuntn84]

Horse Logic: Its worth about 50 fps. So be careful if you're coming up on your max loads.
I got nothing to back that up but that's what I was taught and have yet to blow up yet ;)

[.429&H110]

Great question, good answers!
Much more might be said...
There are hours of reading here on the subject.
Away back when primers were to be found I wasted them shooting glue gun boolits. Magnum primers make a few sparks at the muzzle, was worrysome indoors. The nylon didn't seem to fly any faster. My Speer book says when to load magnum primers, and so I do. My Keith boolit load (H110) does not use a magnum primer, and works fine at -48. YMMV.

[Larry Gibson]

Not "horse logic" but fact.

Note with the 2400 load switching from a Federal 150 LP primer to a Federal 215 LR primer the velocity increased 38 fps whereas the pressure increased 10,800 psi. That changed the loads pressure from a midrange 44 magnum load to a load 5,200 psi over the SAAMI MAP. The chronogaphed increase of just 37 fps difference give no indication of the 10,800 psi increase in pressure. If we look at just the LR primers, standard and magnum, tested with the 2400 load we still see only a 62 fps increase in velocity with the Federal 215 over the CCI 200 yet the pressure increase with the federal 215 primer was 7,200 psi over that with the CCI 200 primer. Again, the chronograph did not really indicate that kind of an increase in pressure.

Just because we are taught something doesn't make it so......

From a test I conducted sometime back with the 44 Magnum having primer pockets reamed for LR primers.

RCBS 44-250-K cast of WWs + 2 %tin with a BHN of 16, sized .430 and lubed with Javelina
WW Super 44 Magnum cases (new) with primer pockets reamed for LR primers
WW Super 44 Magnum cases (new) with standard primer pockets with control loads
OAL; 1.711”
Powders; Alliant 2400 (21 gr) & H110 (23 gr)
Results listed as; primer/average velocity (fps)/SD/ES/average PSI (M43)/SD/ES

H110 load;
Control load;
WLP/1400/24/78/21,700/1,200/3,600

LR primer loads;
Rem 9 1/2/1466/47/112/25,200/3,500/8,500
CCI 200/1390/49/141/22,100/1,500/4,200
CCI #34/1507/35/107/28,300/3,000/9,000
WLR/1506/26/85/28,500/2,300/6,000
Fed 215/1544/12/36/31,600/1,500/4,100

Here we see all the psi’s within SAAMI proscribed MAP. We find the control load with WLP primers to be relatively mild. The hotter Fed 215 magnum LR primer produced the most consistent internal ballistics and the highest psi with the highest velocity with H110. No pressure problems observed with using the LR primers in this load with H110 powder.

Alliant 2400 load;
Control load;
Fed 150/1542/18/51/30,800/1,000/2,700

LR primer loads;
Rem 9 1/2/1603/13/37/34,700/500/1,200
CCI 200/1589/20/46/33,000/1,800/5,000
CCI #34/1634/10/27/37,900/1,900/5,500
WLR/1633/8/22/37,600/1,000/2,600
Fed 215/1641/13/29/41,200/1,900/4,100

Here we see some LR primers (the “soft” 9 ½ & 200) are OK with this load keeping the psi under the SAAMI MAP/. However, when magnum level LR primers are used we see the psi going Over the MAP and the Fed 215 psi going over the MPSM. Note the very good internal ballistics with this load of 2400 with all the primers tested. Obviously, this load is burning very efficiently in the 30K to 41K psi range.

[abunaitoo]

Shooting is majority cast boolets, so looks like I'm safe.
We only have a 100yd range, so no high pressure loads.
Great news.
I can use them and not have to worry.
Thank you all.

[Gator 45/70]

Use to find .magnum primers 2/3 dollars per bring k cheaper so I used them vs rp
I actually think people were hesitant to use them?
I like em

[Petander]

I got dangerously involved in 300 m groups shooting some 20 years ago. It got OCD,never satisfied with the group size. How much under an inch can I get if I do this and that... 215 was the best for me.

Anyway, I loaded a lot 300 WM with Fed 215 and eventually got tired switching primers for 308 ( shot that a lot,moving moose target) 45-70,30-06. So I ended up using 215 for all my LR primered ammo. I did that for ten years or so.

I still load 45-70 with magnums.

[Brokenbear]

Yes it can be done sometimes successfully ..generally more often successful than not .. but what about that one time the Sun, Moon and Uranus are not lined up in your favor on test day? ..just saying be careful when you step out of laboratory proven results

Happy New Year to ALL

Bear

[TurnipEaterDown]

In response to Larry Gibson's post on 12/22:

The 2400 load that you have been testing does likely shed light on the reason that I remember seeing in print in Hercules pamphlets, or old loading books, cautions about not using magnum primers in 2400 loads.
It may even have been in discussion w/ a ballistician 30 years ago that my memory comes from.

I see in the data that you present the following:

Begin Quote:

RCBS 44-250-K cast of WWs + 2 %tin with a BHN of 16, sized .430 and lubed with Javelina
WW Super 44 Magnum cases (new) with primer pockets reamed for LR primers
WW Super 44 Magnum cases (new) with standard primer pockets with control loads
OAL; 1.711”

Alliant 2400 load;
Control load;
primer/average velocity (fps)/SD/ES/average PSI (M43)/SD/ES
Fed 150/1542/18/51/30,800/1,000/2,700

LR primer loads;
Rem 9 1/2/1603/13/37/34,700/500/1,200
CCI 200/1589/20/46/33,000/1,800/5,000
CCI #34/1634/10/27/37,900/1,900/5,500
WLR/1633/8/22/37,600/1,000/2,600
Fed 215/1641/13/29/41,200/1,900/4,100

Here we see some LR primers (the “soft” 9 ½ & 200) are OK with this load keeping the psi under the SAAMI MAP/. However, when magnum level LR primers are used we see the psi going Over the MAP and the Fed 215 psi going over the MPSM.

End Quote.

This places the spread from your control load w/ F150 to the F215 as 10,400 psi mean.
This could be what my memory is recalling about a warning as a pressure excursion. Not an excursion in an individual sense really (shot to shot w/ same primer), but really a mean shift due to changing of primers from published data. That mean shift as you note takes an OK load that you tested to excessively high pressure level for the cartridge.

I wonder if you have tried the CCI350 LP Magnum with this load?
In my test w/ the 475 LL, I saw this as generating the second highest mean indicated pressure. Not that this would translate directly to another cartridge combination, but I am curious.

I also saw the WLP as generating the lowest indicated mean in my test. Did you try this primer in your 2400/44/250K test for comparison?

I do see that you tested the WLP in your H110 load data set, and there it generated the lowest pressure mean for the data you presented:

Begin quote:
H110 load;
Control load;
WLP/1400/24/78/21,700/1,200/3,600

LR primer loads;
Rem 9 1/2/1466/47/112/25,200/3,500/8,500
CCI 200/1390/49/141/22,100/1,500/4,200
CCI #34/1507/35/107/28,300/3,000/9,000
WLR/1506/26/85/28,500/2,300/6,000
Fed 215/1544/12/36/31,600/1,500/4,100

End Quote

I see some similarity between what you present from the 44 testing w/ H110 and what I found from the 475 LL testing w/ WC680, and that makes me want to understand your testing a little further.

[Rich/WIS]

In low pressure/velocity loads probably makes little or no difference. Did notice that standard primers in 243 and 30/06 sometimes caused delayed ignition with BLC2 and Win 748, was noticeable only when wearing electronic muffs. Some had a definite click-bang that would not have been noticeable with standard muffs and plugs. None of these loads were "hot" and a primer change showed no difference worth worrying about. Win primers might be formulated differently as the ones I have seen are labelled for standard and magnum loads. Tried LPM primers in 45ACP when I was burning through some WW452 and WW473 as there seemed to be a lot of unburned powder, but in this case the primer change didn't help. These were low end loads and think the real issue was the load was too light to generate sufficient pressure for a clean burn.

[Messy bear]

Interesting thread. Like to see some of this data in a sticky.
Find Larry to be spot on with the concept that it depends.
Having done some pressure testing in a lab, we found huge differences in LP primers in 45 Colt.
It’s powder specific and you just don’t know. Also found 350’s to be much stronger or hotter as well.
Turnip- would like to see you post your results!
Thanks guys

[dale2242]

I did very unscientific test with CCI magnum vs standard primers in the 45ACP in 2 different pistols.
One was a 1911. The other was Sig P220.
I have no way of testing pressures, but primers looked the same.
I shot these loads for group through a chronograph.
There was no difference in accuracy.
The loads with magnum primers chronographed 20 FPS faster.
In my case, I would use them in my loads.
YMMV.

[243winxb]

https://www.shootingtimes.com/editorial/ammunition_st_mamotaip_200909/100079

A good read on primers.

[Airborne Falcon]

I used-to use a ton of Wolf Magnum small rifle primers when I could get them from Widener's back in the day ... cheap and plentiful. Loved them in 5.56 service rifle loads. IMHO they performed as good, or better, than #41s.

The big question for me has not always been magnum vs standard primers ... but large rifle magnum vs large pistol magnum and so-on and so-forth and how interchangeable are they?

[David2011]

https://www.shootingtimes.com/editorial/ammunition_st_mamotaip_200909/100079

A good read on primers.

Thanks for posting that link. It really is a good article written by someone that has far deeper knowledge than the typical gunwriter.

[Cosmic_Charlie]

Timely thread. I buy magnum primers if that is the only choice these days. So far, using them for medium loads well below max has worked o.k. it would seem. But unlike Larry, I have no idea what the pressures are.

[TurnipEaterDown]

In response to 'Messy Bear', below is the pressure results of the primer test that I ran w/ the 475 Linebaugh Long.
Again, I would urge that this small data set NOT be used as an interchangeability guide, or fixed ranking assessment for other cartridges or powders. I accept no responsibility for use of this information other than as general knowledge.

I wouldn't read too much into the standard deviation numbers for small sample sizes like this. The group number in test was recorded in order to understand if there was a relationship between pressure and increasing number of shots fired. There seemed to be none evident, so no mathematical correlation assessment was made.

Primer Pressure tests w/ 475 Linebaugh Long (1.600" WW 45-70 brass) 400gr LBT WFN (394 gr) 41.5 gr WC680 (lot 47271)
Primer Description / Pressure / (Std dev) / rise / (# shots in group) group number during testing


********* HOT primers
CCI 250 (Large Rifle Mag) 39000 psi (900 SD) 48 msec rise (3 shots) 8
CCI 350 (Large Pistol Mag) 38800 psi (1500 SD) 49 msec rise (3 shots) 11
Federal 215 (Large Rifle Mag) 38300 psi (300 SD) 49 msec rise (4 shots) 2
CCI BR2 (large rifle BR) 38000 psi (2000 SD) 50msec rise (4 shots) 7
Winchester WLRM (L Rifle Mag) 37400 psi (1300 SD) 49 msec rise (4 shots) 4
CCI #34 (Large Rifle Military) 37600 psi (600 SD) 52 msec rise (4 shots) 5
Winchester WLR (Large Rifle) 36900 psi (600 SD) 51 msec rise (4 shots) 13
*********Moderate primers
Federal 210 (Large Rifle) 36300 psi (1100 SD) 50 msec rise (4 sots) 3
Federal 150 (large Pistol) 36300 psi (400 SD) 51 msec rise (4 sots) 12
Federal 155 (large Pistol Mag) 36000 psi (1000 SD) 52 msec rise (4 shots) 1
CCI 200 (Large Rifle) 35700 psi (0 SD) 51 msec rise (4 shots) 9
CCI 300 (Large Pistol) 34800 psi (1600 SD) 53 msec rise (4 shots) 10
**********Mild Primers
Winchester WLP (large pistol) 30900 psi (500 SD) 59 msec rise (4 shots) 6

No cleaning was done between groups. Little leading (insignificant) was experienced.

Primers segregated into "hot","moderate" and "mild" by similar pressure mean in a subjective manner.

[Airborne Falcon]

No other forum on the WWW could do what this thread does. Really good info.

[Messy bear]

Thanks Turnip!
Your test is interesting and mirrors the primers we tested. I am not surprised to see the 350’s in the hot category. I am also not surprised at the WLP being the coldest. Exactly what we found. The problem is when you combine a lower load density with a cool primer. We saw dangerously slow rise times with the WLP. It comes out of it by adding more powder but it’s not as smooth as other primers. In that I mean pressure and velocity jump faster than say a 300 or a Rem 2-1/2.
The Rem turned in best results in our testing.
Granted we were igniting 20+ grains of powder as compared to you.
Is that right that the 200 gave no deviation? Incredible results.
Thanks so much!

[BrassMagnet]

I have to admit I gave up on reading everybody's comments here.
My experience is this: I followed loa data that used CCI LR Magnum primers and I was dissatisfied with the performance. When I changed to stand LR primers my grouping got a lot better.
I can see using them in magnum cases, so I have them.
In shortage times, I will have no problems with using them with any data and middle of the load data loads. Maybe the groups will be larger, but they will still work for 200 yard hunting loads or self defense.