Leaking Primers

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What caused the leaking primers to the right? Primers to the left are normal.

  • Plugged flame channel

    Votes: 3 25.0%
  • Plugged flash hole

    Votes: 2 16.7%
  • Flash hole too large

    Votes: 3 25.0%
  • Primer too tight i.e. head space too small

    Votes: 0 0.0%
  • Primer too loose i.e. head space too large

    Votes: 2 16.7%
  • Flame channel too small

    Votes: 1 8.3%
  • Flame channel too large

    Votes: 0 0.0%
  • Flash hole too small

    Votes: 0 0.0%
  • Too much powder

    Votes: 1 8.3%
  • Ambient temperature too high

    Votes: 0 0.0%

  • Total voters
    12
  • Poll closed .
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Rifle is 45 caliber Omega. First shot was from a cold clean barrel. Primers were used in the 'Shoot the Gong' thread. Load was 115g Blackhorn, 200g Shockwave, Harvester light blue sabot, SST primer. NO, no STS, primer is what was used. The breech plug has had the flame channel enlarged to 5/32". An o-ring was used in the primer seat. The flash hole was/is 0.032" .
 
Top item would be headspace bit a restricted flame channel volume would do it also. But using having to use oring says alot. Have you adjusted lockup of action to barrel face
 
I am wondering what primer are those and are they Mag primers? I did not think you used Mag primers so they are probably not.

Besides the leaking I look at the primers and notice the dis-coloration of the battery cups. They appear to have gotten very hot and even stressed in the area of tip of the anvil to the bottom of the actual primer, actually from the anvil all the way up battery cup. So my first thoughts are excessive back pressure. Or another thought is that the hot primer gas could not vent properly (or fast enough) through the BP & Flash Hole. I might actually exect that if they were mags.
 
I picked plugged flame channel, but I'm probably wrong. My guess is that its very unlikey that Ron's plug is not clean. So maybe its due to improper fit (too loose)?
 
sqezer said:
:think: I can't pick just pick 1 I need to pick 2 plugged flash hole & flame channel. :yeah:

After looking at the primers on the right ( and I think Ron is a great guy & tinkerer, ) I see that the front sides of the primers have a shine on them, he has a great seal in the breech plug but the HEAD SPACING is incorrect, did the O-RING fall out. :think: Is it a plugged flash hole or plugged flame channel or an OVER CHARGE OF POWDER? I'm going with a SPIT BALL. :goodman: :poke: :yeah:
 
I think GM54-120, has solved the case of the leaking primers:

Originally Posted by Gm54-120 View Post
1) A 5/32 flash CHANNEL works fine in a variety of plugs even at higher pressure.

2) The anvils are not pushed back out of the cup so head space is fine.

3) Leak appears to be from between the anvil and cup which leads me to believe the cup is expanding just enough to allow some blowby.

4) I would like to see a Win209 primer shot from the same plug with the same load. The Win209 cup may be slightly larger OD and/or slightly tougher than the STS primer's cup.

If i can shoot loads all day that break 30Kpsi with a Win209 or Fed209A in a Savage plug and with my NULA using CCI 209s, i cant imagine its the ID of the flash channel and a sub 22kpsi load.

Scott, I think you have solved the problem... knowing Ron and his experience - I believe there is no way that he had a restricted 'flash channel' and the .032 'flash hole' is perfect. His powder load and bullet weight really should not have caused excessive blow back or pressure. I never voted in the poll but if your suggestion were added to the poll it would get my vote. Your explanation would also account for the metal discoloration under the rim of the battery cup.

I did not mic it - but I just dropped a STS primer in an Omega BP primer hole - it is quite loose... Remington's have a battery cup diameter of 0.240 while W209's are 0.242. Euro primers (Cheddite-Fiocchi-Rio's) run a little fatter at 0.243/0.244.

Nice job Sherlock!
 
sqezer said:
sqezer said:
:think: I can't pick just pick 1 I need to pick 2 plugged flash hole & flame channel. :yeah:

..... or (AND) an OVER CHARGE OF POWDER? :goodman: :poke: :yeah:

Bingo
Yahtzee
Kismet....... along with escalating plugging of the flash channel and flash hole. In looking at the spent primers from only one angle shown, one can almost see which were used first - which used last.
 
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Did some shooting this morning with 3 different primer brand. Once again the shooting began with the same cold clean 45 caliber Omega rifle, and breech plug. The same bullet, sabot, and powder was used as in the original post. The breech plug' flash hole has now grown to 0.033". The flame channel is still 5/32". Before the breech plug was installed into the rifle, it was shortened 0.020", which reduces the head space, and necessitates the use of an o-ring. There was zero blow by around the nose of all three primer brands, because of the seal provided by the o-ring. However the STS leaked. Neither the Federal, or the Winchester leaked.


After the 10 shots, the breech plug was removed in the field, yes a tool was needed, and replaced by a brand new factory breech plug. No o-ring was used in this shiny new breech plug. Using the same load, three shots were taken with each primer brand.




IMG_0200.JPG





As before, the STS primers leaked. Neither the Federal 209A, nor the Winchester W209 primers leaked. There was some blow by around the nose of the 209A primer, but none around the W209.
 
Ive had the best luck with Win209s and FED209As in the largest variety of MLs. One SML uses CCIs but it was machined to fit them with tight tolerances.

My best guess was the STS battery cup was weaker than some 209 primers. That guess appears to be correct since the Feds and Wins are basically fine with the same load and breach plugs. I have a few STS primers, i will take some with me next time and try them in my Super DISC.
 
Rifle Change

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This morning, those STS primers were tried in a different rifle, the Optima V2. The load was the same as in the OP; 200g Shockwave, and 115g Blackhorn. The sabot needed changing to Harvester dark blue, because the Optima is a 50 caliber. Note, there is zero leakage through the primer!



Then the notion came to try a heavier bullet, and see what happened. There were some 300g XTP rolling around in the truck, so they went into the rifle. The primer stuck in the breech plug. The load was 115g Blackhorn, 300g XTP, Harvester short black sabot, and the STS primer. All three times, the primer stuck tight in the breech plug, and required a leatherman. The primers show the marks on the rim, which were made by the leatherman tool. Even using the tool, removing the primers took a bit of effort. Note, the primers didn't leak.




IMG_0211.JPG









The previous 6 shots were all made with an o-ring in the primer socket of the breech plug. The next 3 shots were done after removing the o-ring from the primer socket. There were no more XTP, so 300g Deep Curl from last hunting season were used instead. The load was 115g Blackhorn, 300g Deep Curl, Harvester short black sabot, and STS primer. These primers could be pulled some out of the breech plug, but fingernails were already busted up from the previous primers, and the leatherman was handy, so the primers were easily pulled with the tool. Note these STS primers didn't leak



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Those looked bulged...you can see the firing pin bushing mark in the cups....plus the second picture looks like thy leaked on the cup edges,,,you know it could a bad batch of primers...or the head space is not correct....

AL
 
The firing pin bushing in the Optima has large gaps; it is 'normal' for the primer to 'flow' into the gaps when fired.

The primers in the second photo were 'locked' in the breech plug, and were very very difficult to remove. The marks on the edge of the cups are from the plier used to wrest them out of the breech plug.

The primers in the third photo do indeed indicate 'excess head space'.
 
yes i was talking about the last pics with the bushing narks in it...but the STS primers seem to be leaking at the cup also...

just for HAHA's try a 100 grain load and see what the primers look like...
 
Conclusions

  • 1. Chances the flame channel was plugged are near zero; the rifle was cleaned before the shoot.

    2. Never have seen a plugged flash hole from shooting Blackhorn... probably over 35 pounds have been burned.

    3. The flash hole was 0.032", which many feel is perfect, not a problem... not too large.

    4. It seemed the head space might be too tight, but the next day the primer still leaked when the o-ring was removed... didn't seem to be the problem.

    5. Doesn't seem the head space would be too large, after an o-ring was added, plus the anvil stayed in place in the cup.

    6. The flame channel wasn't too small; it was larger than new... at 5/32".

    7. Enlarging the flame channel would reduce the pressure on the primer; doesn't seem an enlarged flame channel would cause the primer to leak.

    8. A flash hole larger than new, wouldn't seem to be too small.

    9. Too much powder is probably the best of the available choices.

    10. It was a cool morning, so the temperature wasn't too high.






Following is what i believe is the very best answer.

GM54-120 said:
....Primer pocket is slightly over sized or simply not supporting the area near the rim of the primer enough.....
 
Re: Conclusions

ronlaughlin said:
9. Too much powder is probably the best of the available choices.


Just to be clear, I was the only one that voted for this. Ha!
 
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