Magnum primers

[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/editor..._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/editor..._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.