plastic flow of primer material

[Window]

Yes, most instances of guys blowing up trays of primers have been with federals. (if memory serves)

They are sensitive little guys.

Sure is nice to have all that fire when you need to ignite a difficult powder in large quantities. H50BMG and Retumbo in cheytac cases will hang-fire a CCI-250... but Fed215 and 215M will pop reliably every time.

These days I recommend Fed215M for everything above 75gr of powder, and/or anything slower than H1000. Otherwise I run a steady diet of CCI-200 for up to 45gr capacity and 250 in everything else. Pretty much standardized exclusively on CCI-450's for everything smaller, regardless if I need magnum or not.

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They'll also hang fire with 102.5 grains of H1000 in a 30-378. Don't ask me how I know.

 

[Window]

try primer sealer before you prime. I've done this with no blow out. I have old FC cases in 300WSM with many firings when there is little resistance, I just seal the primer pockets.

What primer sealer are you using?

 

[Window]

when I compare fired and unfired dia. at the top and bottom of the body--- (just below neck and just above belt) the unfired rounds are all .006 undersize. Fired are close to the diagram in the lee manual. (+or- .001) The primers in both the fired cases -- AND unfired cases are so loose I could probably push the primer in with my fingernail. That aint right. Going to call federal tomorrow ------

I've seen that in Weatherby factory rounds as well.

 

[VarmintBob]

When the primer cups look like poured pancake batter, that is a real sign of high pressure. Should see case extrusion into the ejector hole too.

 

[levers4life]

try primer sealer before you prime. I've done this with no blow out. I have old FC cases in 300WSM with many firings when there is little resistance, I just seal the primer pockets.

Seems like a work around that isn't necessary with Hornady, Remington, Winchester, Lapua, Norma or Peterson brass as I've never had that problem with these brands. Simple fix, stop using Federal.

 

[Dean2]

The OP has clearly said that the primers are loose even in the unfired factory rounds. Unless you guys don't believe that, then the brass is clearly defective. Has nothing to do with brand, it is badly made and out of spec. While i also don't like Federal brass for many of the reasons enumerated, in this case the brand is a distraction. This has happpened to many other makes of factory loads and it is why recalls on factory ammo is fairly common.

 

[skipglo]

Helping someone zero their savage 110 in 7mm mag.
He was using some kind of federal. ( I will see the box again
tomorrow) I shot 7 rounds. He didn't have any empty brass so I kept the brass to reload for him. Upon examination of the brass - the primers were fairly well flattened back to the edge of the firing pin and at the outer edges. This gave the impression of a max load. One of the primers showed a further artifact. the brass in the primer had showed plastic flow--- and the material at the outer edge of the primer has flowed out formed a little flap of "foil". It was standing outward like a burr when I first noticed it. I expect it was pushing out between the case head and the bolt face. The perimeter of the primer beside this extrusion showed a lumpy raised area like it just starting to flow.

This is factory ammunition. Now I am asking --- why ?

Two things come to mind. First is---- maybe the ogive is in the lands
when the round is chambered. If it is all ready a max load of powder---
that could give the pressure a kick upwards--- right ? So I will try an unfired round-- measure OAL before and after chambering-- see if it sets back. and I will also ink the ogive and see if I can see rifling marks in the ink. Those two should tell me if the round it loaded too long.

the other issue i am wondering is if the barrel could have lead build up from the previous owner. I took a bright flashlight and shined it in at near right angle to the muzzle and I could see some white looking
residue in the grooves. It didn't look like copper-- as much as it did lead according to the color. I don't understand who would or could shoot lead bullets out of a 7 mm. anyway I cleaned the whole gun and scrubbed the bore for about 20 min with Iosso abrasive bore cleaner. Then did hoppies. It looked somewhat better after. But its very hard to get the light angle right to see in there very far. maybe I need to get it bore scoped. (mine is too big to fit inside) Didn't have any sweets copper cleaner.
I am thinking if the bore is slightly fowled somehow-- that would drive up pressures. I am considering putting a stopper in the muzzle and filling it up with something like CLR to attack the fowling. I have never had to get that "tough" with a bore before---- if I use that how long is a safe time to let it sit ?

This gun was bought used-- so there is that chance it had a hidden problem and that was kept hidden and just sold to the next guy.

My intention was to load him some reduced (like starting loads) using 139 grains at about 2600 to make it easier on his shoulder. But if these things are giving high pressure-- the bad recoil may be another sign of
a problem.

Opinions ?

NEVER use CLR....fill it with Hoppes No.9 maybe instead...

 

[kfd518]

Just my two cents,
At one time building a rifle I had some primer issues similar and thinking my bottom end loads were too hot already. It turned out the chamber is a hair long not NO GO long but not tight. When the FP hit the primer it would shove the case forward allowing the primer to back out slightly then as it expanded the case lengthingening to fill the chamber would try to re-seat the primer this caused big flat wide primers. Check the head space. Especially since most factory ammo is made to minimum saami AMMO spec belted mags can stack brass headspace quite quickly.

 

[Hugnot]

I shoot lots of 1X fired Federal 6.5 CM small primer brass & the primer pockets are acceptable but much looser than Lapua. The force needed to seat varies with primer make.

A photo showing black between primer & brass would help.

I have some reformed 1X fired Federal .30-06 to 6.5-06 that worked out just fine with near max loads. These were FC reformed .30-06 to 6.5-06, 130 HELDM, 57.8 Staball HD, CCI 34 primer. The CCI 34 primer is a NATO spec primer used in 7.62 ammo - tough hard sparky primers used in the M60 & like. Estimated pressures about 60K PSI, velocities just over 2,900 fps for these 6.5-06 loads. Necks turned to .287. Note radial marks on brass shoulders (carefully adjusted head-space), mild primer cratering, primer flattening, but no black crud.

Shoots beautiful. Near max loads. Got a small bucket full of FC 06 brass. I also buy 1X fired 5.56 Federal brass having crimped primers & swage out the crimp, doing this gives me some indication of how hard this brass is

 

[memtb]

Just my two cents,
At one time building a rifle I had some primer issues similar and thinking my bottom end loads were too hot already. It turned out the chamber is a hair long not NO GO long but not tight. When the FP hit the primer it would shove the case forward allowing the primer to back out slightly then as it expanded the case lengthingening to fill the chamber would try to re-seat the primer this caused big flat wide primers. Check the head space. Especially since most factory ammo is made to minimum saami AMMO spec belted mags can stack brass headspace quite quickly.

This often happens with factory ammunition! With the cases sized as to fit any (supposedly) all factory chambers…..they're typically pretty loose in the chamber! memtb

 

[memtb]

Also, I never store too much faith in using primer appearance as the "end all" sign for pressure. Perhaps a point at which I'll start to be a bit cautious!

Primer cups vary in thickness, metallurgy, metal temper, ect. memtb

 

[evodude]

@Catbrain, I don't suppose you chronograph the factory ammo speed to compare to box label?

About always different.

 

[Jasbo]

This often happens with factory ammunition! With the cases sized as to fit any (supposedly) all factory chambers…..they're typically pretty loose in the chamber! memtb

Amen! My 338RUM Rem 700 BDL Factory Chamber yields fired brass 0.023 longer than ADG new using the Sinclair headspace gauge. Another reason to Neck Size!

 

[esshup]

Buying used rifles are always a gamble in my book. A buddy bought a used 7 Rem Mag Sendero, and he showed me some of the brass that was fired in it. Primer tried to extrude into the firing pin hole. I thought it could be saved by machining a bushing, but the gunsmith/machinist he took it to said no, he was better by getting a whole new bolt. I've had the same guy do some work, and I trust his work and judgement.