Excessive pressure from primer switch

[Harvey_NW]

Has anybody ever experienced excessive pressure from switching a primer?

The details - recently been trying to find a load for my 28 Nosler. I bought 100pcs of factory new pulled/primed Nosler brass from another member, and my plan was to test a few combos to form brass out and see if it showed any promise. After popping the primers out to resize brass I concluded they were CCI 250, called Nosler and they confirmed. Got some pretty good group results using H50BMG with 180 VLD, Min 85.2 - Max 90.6C Hodgdon data. My load I set the ogive .060" off the lands. Initially I shot:
86 - avg 2980
87.5 - avg 3020
89 - avg 3063
No pressure signs at all and good results. Problem is, I don't have any more CCI 250.

Fed 215 test - based on past experience and advice from others, middle of the road charge should be safe and not much different from the original test. First shot:
87.5 - 3182, noticeable increase in recoil, flattened primer, bolt lift.
Shot #2 - 3160, same thing.
160 fps increase at the same charge weight. Called it quits.

Went home and loaded some with Rem 9 1/2's and went back to the range, they seemed to be in the middle. I was getting about 40-50fps faster with the same charge weights and CCI.

The only difference I noticed is the CCI's that were popped out and reseated had much less resistance than the Fed 215's, or Rem 9 1/2's, but no gas blowby in any of the pockets.

Thoughts or experiences?

These are the 4 pcs fired with 89gr/CCI for reference

 

[ResearchinStuff]

those primers with the ccis look pretty flat, with raised craters, and the furthest left case has an ejector swipe. Case #3 might have a slight ejector mark too. it seems like those loads were too hot to begin with.

 

[BRTreedogs]

I know shipping is an issue.
But I would say more people are looking for 215s then 250s
If you have a supply of 215s id bet you could do some trading

 

[Harvey_NW]

those primers with the ccis look pretty flat, with raised craters, and the furthest left case has an ejector swipe. Case #3 might have a slight ejector mark too. it seems like those loads were too hot to begin with.

The crater is consistent across all charges, the swipe happens from just chambering and ejecting a loaded round. The ejector marks are faint and consistent as well across all charges, except the Fed 215 cases had both ejector marks fairly pronounced.

 

[Harvey_NW]

I know shipping is an issue.
But I would say more people are looking for 215s then 250s
If you have a supply of 215s id bet you could do some trading

If the load proves itself with that combo, that's the route I'll be taking. Just perplexed by the issue, never seen such a drastic swing.

 

[BULLBLASTER]

Was the brass all new with the 215s? Or was it once fired compared to new with 250s?

 

[Harvey_NW]

Was the brass all new with the 215s? Or was it once fired compared to new with 250s?

New with both, all comparisons are apples to apples.

 

[BULLBLASTER]

It seems like something else is causing a spike. Did you shoot any of the 250s on the same day as the 215s? Ive never seen anything near that velocity jump from a primer switch.

How many rounds were shot with the 250s to get your averages?

 

[Bluefish]

Same temperature for all the testing? I found out that cfe223 is a bit temperature sensitive last year. Summer loads were 100-125 fps faster than hunting season loads.

 

[Harvey_NW]

It seems like something else is causing a spike. Did you shoot any of the 250s on the same day as the 215s? Ive never seen anything near that velocity jump from a primer switch.

How many rounds were shot with the 250s to get your averages?

(3) 86, (3) 87.5, (4) 89 with 250's. Tested the Rem 9 1/2's same day up to 88.5, 87.5 had a 4 shot avg of 3060, so the only factor on the spikes were Fed 215's.

Same temperature for all the testing? I found out that cfe223 is a bit temperature sensitive last year. Summer loads were 100-125 fps faster than hunting season loads.

Within 10°, all of this testing was done in the last 2 weekends. Weather has been pretty consistent, and H50BMG is an extreme powder.

 

[t_carlson]

What kind of chronograph are you using and what does the load data say your velocity should be at?

 

[Harvey_NW]

What kind of chronograph are you using and what does the load data say your velocity should be at?

ProChrono that I've compared to a magnetospeed and shot many other rounds over, always been accurate and repeatable. My barrel is 2" longer and tighter twist than the load data, so the velocities with the 250's and Rem 9 1/2's look to be normal, the Fed 215 is the outlier.

 

[zrodwyo]

I would be checking for a carbon ring. Especially since it’s a 28 nosler.

 

[Flyjunky]

I would be checking for a carbon ring. Especially since it’s a 28 nosler.

Exactly what I was thinking. Although I wouldn’t expect it to suddenly appear between groups like that.

 

[Harvey_NW]

I would be checking for a carbon ring. Especially since it’s a 28 nosler.

Cleaned before I started testing and only have about 40 rounds on it, I'm not sure how people are missing the rest of the context but I said I immediately followed up with testing Rem 9 1/2's and didn't get the high pressure results. It was directly related to the Fed 215's with 2 shots being noticeably different with chrono data to support them.

Exactly what I was thinking. Although I wouldn’t expect it to suddenly appear between groups like that.

Me either, which is why I tested a 3rd primer too.

 

[Flyjunky]

Strange, I’m not sure what to think. I’ve never experienced that kind of difference in primers.

 

[Vern400]

Has anybody ever experienced excessive pressure from switching a primer?

The details - recently been trying to find a load for my 28 Nosler. I bought 100pcs of factory new pulled/primed Nosler brass from another member, and my plan was to test a few combos to form brass out and see if it showed any promise. After popping the primers out to resize brass I concluded they were CCI 250, called Nosler and they confirmed. Got some pretty good group results using H50BMG with 180 VLD, Min 85.2 - Max 90.6C Hodgdon data. My load I set the ogive .060" off the lands. Initially I shot:
86 - avg 2980
87.5 - avg 3020
89 - avg 3063
No pressure signs at all and good results. Problem is, I don't have any more CCI 250.

Fed 215 test - based on past experience and advice from others, middle of the road charge should be safe and not much different from the original test. First shot:
87.5 - 3182, noticeable increase in recoil, flattened primer, bolt lift.
Shot #2 - 3160, same thing.
160 fps increase at the same charge weight. Called it quits.

Went home and loaded some with Rem 9 1/2's and went back to the range, they seemed to be in the middle. I was getting about 40-50fps faster with the same charge weights and CCI.

The only difference I noticed is the CCI's that were popped out and reseated had much less resistance than the Fed 215's, or Rem 9 1/2's, but no gas blowby in any of the pockets.

Thoughts or experiences?

These are the 4 pcs fired with 89gr/CCI for reference
View attachment 530180

Not surprised at all. I've seen that in smaller 30 cal cases before. It's easy for a primer change to make a big difference. I've also seen a proven primer dislike a new powder. For example I use federal 210 primers with varget and reloader 15. With IMR 4064 the Remington primers group better for me and give me lower ES. I tried everything to get Federal 210's to work with 4064 and they just didn't want to do it.

 

[eschafer]

Which shots fired were with virgin unfired brass and were any shots fired with once fired (fire-formed brass)?

A fair bit of energy from the charge is needed to fireform the brass to fit the chamber (on first fire). That same charge weight can produce pressure signs on once fired brass since the brass has nowhere to go in the chamber (already expanded).... Try dropping charge weight, if you used once fired bass second time out...

 

[SwiftShot]

Never seen primer change do that big of a change. If the only difference is the primer, well it must be the primer. You say nothing else changed, well then it is the primer. I could see it if you had moved from a large rifle to a magnum but just brands should not do that, but apparently it can.

 

[zacko]

I accidentally loaded 215s in my saum with my 210 load and the velocity jumped 75fps es went wild as did sd. I realised fast what had happened as I'd asked about the primers when I noticed they were purple not red and a friend had assured me he didn't have any 215s they were already in his priming tool which had ment 75 had gone into his last sitting at the bench