Primer Flattening question: Do any of these appear flat or problematic in any way?

[peppercorn]

I have noticed that not all of my primers look the same after being fired.
I have tried to photograph a representative cross section of what I mean, as seen below.

The primers represented are Winchester, Federal and CCI.
All of my loads are within published data spec, the hottest being 20.6 grains of 2400 and the mildest being 9.2 grains of Unique.
These were fired in either a 629-6 or a 29-3.

Thanks for any and all input.

 

[Treeman]

Those look "mild". Primer flattening is very much a matter of comparing the SAME primers in the SAME gun. A lightly sprung revolver with a bit more headspace than some(not talking excessive/out of specs) can smush primers to a fare-thee-well with loads that are well under maximum pressures. (A matter of the primer explosion backing the primer partway out the pocket and then powder combustion slamming it all back against the recoil shield) If primer POCKETS are stretching /getting loose in a fireing or two then you know that you either have soft brass or high pressures(OR BOTH)_
The Primers in your pohoto seem quite unremarkable. (YAY!)

 

[buck460XVR]

The Primers in your pohoto seem quite unremarkable. (YAY!)

I hafta agree. Shoulders are still nicely rounded. Different brands of primers have different resistance to flattening and even within the same brand, the cups of magnum primers may be harder than those of standard primers. That may be why they appear different. Primers in a revolver are a poor judge of pressure, but those primers are obviously from safe loads. When your primers are completely flattened with no visible shoulders and you need to drive the empty cases outta the cylinder with a dowel, then you have pressure issues.

 

[Titegroups]

When the primers flow out into the radius of the pocket them your pressure is running high, use primer info as a relative measurement rather than an absolute. A chronograph can also give you insight into whats happening with velocity. Also watch for sticky extractions. There aren't any great ways to check for pressure except with purpose built equipment thats why its important to stay within manf. specs.

 

[venomballistics]

When the primers flow out into the radius of the pocket them your pressure is running high, use primer info as a relative measurement rather than an absolute. A chronograph can also give you insight into whats happening with velocity. Also watch for sticky extractions. There aren't any great ways to check for pressure except with purpose built equipment thats why its important to stay within manf. specs.

i'll second this ... primers give you an idea of pressure while a chrono gives you a closer one. the ultimate tool is a universal receiver.
now on to the pics ... so ... when are ya going to get serious?
honestly contestant number 3 looks like its a load that wants to run ... nice pressure so it'll likely be a rather uniform load ... run a good string of those over a chrono and look at the string of primers ... that looks like a load that might run with swiss precision ... investigate it

 

[ArchAngelCD]

None of those primers appear to be showing any pressure signs.

Just a note, Winchester primers sometimes appear to be flattening but they only appear that way and it's not pressure causing it. You will see this especially in .357 Magnum ammo, even in Winchester Factory .357 Magnum ammo.

 

[peppercorn]

Great information everyone, thanks so much for the feedback.
I am relieved to read the consensus that these primers appear to be within normal limits. Being new to this game I am starting to see that I am tending to over analyze some things and under analyze others.

I will continue to 'work up' loads within published data spec.
I will also, as I approach max loads, pay more attention to which primer went with each fired recipe. So far they have all sort of ended up in one big ziplock after they have been fired.

 

[OKFC05]

Agree with the above comments, but feel obligated to point out that reading pressure signs as done with bottleneck rifle cartridges is notoriously unreliable with straight-walled pistol cartridges.

You can often go way over safe pressure limits with no signs whatsoever, and the first sure sign on a revolver may be the topstrap hitting the ceiling. Reloading manuals are our friends.

 

[wheelgun28]

Why do some of the primer hit look off center?

Is it an illusion or a problem?

 

[Rule3]

Does anyone have good pictures of obvious overpressure flattened primers? It would be good for comparison.

There are some in the manuals but they are not as detailed a picture as Peppercorns fine photos.

 

[peppercorn]

It's not an illusion, some of the primer hits are off center. Is this a problem?

 

[wheelgun28]

It's not an illusion, some of the primer hits are off center. Is this a problem?

It could be?

It might be that the gun is firing with the cylinder out of position.

Does it spit lead?

You need to check the timing on each chamber. The timing could be off or the lock up could be slow or a few other things.

I think this has come up a few times in the gun smithing section.

 

[peppercorn]

It could be?

It might be that the gun is firing with the cylinder out of position.

Does it spit lead?

You need to check the timing on each chamber. The timing could be off or the lock up could be slow or a few other things.

I think this has come up a few times in the gun smithing section.

I see that the Winchester primers, one more than the other, are off center. All of the Winchester rounds were fired through a new off the shelf 629-6. No 'peeling' lead from this gun though.

Last weekend I fired some plated, 'xtreme', bullets through a 29-10, also new off the shelf. It was peeling plate to the point of drawing blood on my cheek.
This also happened a few weeks back with a friends PC 629, same bullet. He made note that the cylinder throats are tight on that particular gun however.

More interesting observations.

 

[fredj338]

All of those primers look fine. These are flattened primers:

 

[Rule3]

All of those primers look fine. These are flattened primers:

Thanks, clearly see the difference.

 

[fredj338]

It's not an illusion, some of the primer hits are off center. Is this a problem?

Not really. COnsider you have six chambers, not all are going to be perfectly aligned in relation to the firing pin. Close is good enough.

 

[one eye joe]

To me, the pressure looks fine--the primers are "normal". NONE of the strikes appear to be perfectly centered, IMHO. If you oriented all the cases in the same position in each chamber by using a magic marker line at say 6 o'clock--do all the fired cases appear identical when lined up side by side and oriented the same way? ? ? I think that they might. Then, I would think that the firing pin is just hitting the primers a bit off center because it's not EXACTLY aligned to the centerline of the bore. NO BIG DEAL...........

 

[Titegroups]

All of those primers look fine. These are flattened primers:

Now that's what I'm talking about. Those are flat and flowed.

 

[peppercorn]

All of those primers look fine. These are flattened primers:

Thanks for this photo. I did a google search within the forum and failed to come up with a representative picture.

The primer strike/centering explanations above, yours included, have put my mind at ease also. It looks like it is time to get back to the reloader now.