Primers partially popping out, again.

H4831

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The three on the left, Federal factory load "blue box," fired in a like new, few years old, Browning A Bolt.
The two on the right are my handloads, also Federal brass, multi time use, full length resized with RCBS dies and fired in the same rifle, as a test.
In another thread it was suggested light loads were responsible for the primers popping out. Surely, factory loads wouldn't be that light, would they?
Note the factory loads show distinct cratering. The handloads, in particular the first one, plainly shows the cratering had occurred, but pressure has flattened it.
What do you say?
FC.jpg
 
Surely, factory loads wouldn't be that light, would they?
FC.jpg

The factory 30-06 loads I have run over the chronograph do seem to point to some pretty light loading. This is probably due to the thousands of old - and getting older - 30-06 chambered rifles still in use.
 
Wow it looks like the primers in the first three are even flowing into the firing pin hole. What with the little curl on the crator rim. I hope you didn't buy a case of that stuff!
With primers that soft I wonder where they were made? "Canchi" canadian - made in China or Canexico.
I hope you are plinking with them and are in it just for the brass. If I had a bunch more of those I'd be inclined to pull the bullet and decape the brass and start a fresh.
 
30-06 cartridges have always been loaded lighter than similar calibres, because of the worry about the strength of some old rifles. In particular, some of the very oldest Springfield rifles that had improper heat treatment on their actions. Also, the 30-06 has at some time, been manufactured by every country that makes sporting rifles, in every type action ever devised.
American reloading books, especially the newer versions, all show light, often very light, loads for the 30-06, for the same reason.
The opposite is true of the 308. All new rifles out there, so load them up. If the 30-06 was loaded to 308 pressures there would be a much greater difference between the two calibres.
Actually, I think the first 308 commercial loadings were heavier than the current loadings. I know the gun writers of the day would say that handloaders may not be able to duplicate factory velocities with the cannster powders available, since Winchester had to devise special powder for the 308.
I have no idea of the velocity of the Federal loads shown. The rifle and shooting is my grandson's. He gave the cases to me to look at, because they didn't look normal.
 
A few weeks ago I had went to the range, on my way out I had went through the brass buckets cause I remembered these guys a few bays down were blasting off a ton of 30-06 from their bolt gun. I scooped all the brass. I remembered about them now and they all look like those blue head stamped stamped ones in your pic.
 
It looks like the primers didn't back-out from the pocket but rather bulged. And the brass didn't back-out into the bolt face either.
Maybe the blue sealant has some adhesive properties?
 
It looks like the primers didn't back-out from the pocket but rather bulged. And the brass didn't back-out into the bolt face either.
Maybe the blue sealant has some adhesive properties?

You're right, the primers never moved and even the bulge is misleading in the pictures. The bulge only protrubes about .005, which is pretty well just the crater.
 
FC cases = Federal primers = soft primers? Perhaps those you loaded used CCI's?

(I've slamfired with Fed primers in my M14s, and then found (on this site no less) that people found Federal primers were soft, then stayed with CCI...)
 
I forgot to mention that in my original, or other postings, I failed to mention that the primers used in my handloads and shown in the picture, are Federal, standard rifle primers.
 
Have a look at this link. I suspect your issue is covered in the discussion. My guess would be that it is a combination of a couple of things. The factory load is likely slightly off max for pressure -- not a very light load, but off max. The other factor is excessive headspace. The sequence would go like this. The firing pin slams into the back of the casing, forcing the cartridge ahead as far as the bullet and/or shoulder will allow. The pressure developed is sufficient to expand the case to allow it to grip the cylinder walls (and they could also be a little rougher than normal), but not enough to force the cartridge back against the bolt face. The primer holds well which suggests it is a very tight fit in the primer pocket, but bulges under the pressure. The crater is likely a result of the gap between the cartridge and the bolt face.

Your reloaded case likely has less headspace (especially if it was neck sized only), and the bullet may be loaded closer to the lands. This keeps it tighter to the bolt face. And, the pressure may be higher, forcing it back against the bolt face in any case.

There would be a few ways to test this theory. On the factory cartridges lubricate the case wall with a thin film of sizing lube. This should let them slip back to sit against the bolt face on firing. Or on a reload, neck size only and/or seat the bullet against the lands to control the firing pin movement.

Hope that helps,
 
Note the factory loads show distinct cratering. The handloads, in particular the first one, plainly shows the cratering had occurred, but pressure has flattened it.
What do you say?
FC.jpg

Maybe try a starting load with the same F210 primer and fire it in the same rifle. If it has a crater with a burr on it like the factory loads did, you know it is from a light load. The impressions left by the firing pin on the factory primers look like they're about 20% larger (not including the crater), so I'd suspect those factory primers were an extra soft batch.
 
I'm suspicious of the sealant. If a rifle has a tiny bit of headspace, the primer moves back then is pressed back by pressure forcing the case to stretch over it.
If the sealant was enough to prevent the primer from moving, it may have bulged instead, and not had enough pressure to overcome the sealant.
Determining the amount of brass growth would give some clue to this. If your higher pressure handloaded case grew quite a bit more than the factory load due to stretch, it may indicate that the low pressure of the factory load did not have enough to stretch the brass back and flatten out that primer bulge.
 
Perhaps both Federal primers, but they don't look like they've acted alike and I would suspect that they are different lots or makes with the Federal Brand on the label. To me the home loads don't really appear to have any problems, small items aside. Maybe test fire a ladder set of rounds with your suspect primers and rifle to see results of the min to max spectrum.

Interesting about the blue glue, as mentioned in previous posts.
 
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