Has anyone experienced blown primers with factory ammo?

AP said:
Well read the first few paragraphs of this...
http://forum.accurateshooter.com/threads/pierced-primer-help.3851213/ in the reply referencing the Sierra manual
Also check your firing pin protrusion I believe it is adjustable on some savages
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"Pierced" primers... poor terminology! Incorrect terminology in the vast majority of cases... in the picture they show a primer with the center of the primer firing pin indent missing... the firing pin did not pierce the primer, the primer punched back into the firing pin hole because of a weak firing pin spring and sufficient pressure... but what should that be called? I have heard the term "blank". As in the primer punched a blank or the primer blanked.

Even with a poorly shaped firing pin tip, the firing pin doesn't pierce the primer, the primer may fail and force pressure out in the indent due to insufficient support from the tip.

There has to be a better term...
 
guntech said:
"Pierced" primers... poor terminology! Incorrect terminology in the vast majority of cases... in the picture they show a primer with the center of the primer firing pin indent missing... the firing pin did not pierce the primer, the primer punched back into the firing pin hole because of a weak firing pin spring and sufficient pressure... but what should that be called? I have heard the term "blank". As in the primer punched a blank or the primer blanked.

Even with a poorly shaped firing pin tip, the firing pin doesn't pierce the primer, the primer may fail and force pressure out in the indent due to insufficient support from the tip.

There has to be a better term...[/QUOTE


all very true ... but result is pretty much the same -- a hole in the primer. the other cause of a 'blank' is a firing pin hole that is too large for the firing pin...... but I think the lesson here is that it may not be the ammunition ...( or it may :) .. as far as firing pin protrusion being a cause ... some say not likely as the forward motion will be arrested internally by the bolt.... OTOH its certainly worth ensuring that pin protrusion is not excessive.
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Thanks for all the input guys, keep it coming!
Just to address some of the suggestions, and to clarify some details: bullets seem to slip into fired cases about the same as any other rifles I have.
The cases with blown primers were actually blown, as in the case heads no longer fit into a shell holder.
I left a voice mail with Savage Canada a few weeks ago about this issue, and had no reply, next step will be an email to Savage's main site.
 
guntech said:
This above quote is referring to semi auto rifles out of time 'dropping' a primer.

Excessive headspace won't blow a primer pocket larger, it may cause a primer to back up, flatten and leak. What I call a blown primer is when the primer pocket has enlarged and won't hold a primer any longer.
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it does mention dropping out of primers in a semi auto , but first line of the paragraph above the section I quoted was this .

"The other day I was testing a rifle from Accuracy International and blew a primer. "

as far as I know Accuracy International only does bolt actions . and to me the article dealt with all sorts of primer issues , including mentioning semi autos , but not exclusive to semi auto's .

regardless of opinion , it only takes a couple of minutes to check the headspace and either eliminate it as a issue , or adjust and fix a headspace issue and see if it eliminates the problem .
 
Blanking is seldom because the hole is larger than the pin but is because the hole is large, period. Even if the pin fills the hole, blanking is likely to occur. When blanking occurs due to an improperly shaped tip, it is usually because the tip has partially sheared and threfor, weakened the primer cup. Sometimes. primers are pierced and this is a purely mechanical cutting of the primer cup by the pin. I have seen cases where a primer blanked and the firing pin was flame cut. After that, primers were pierced by the damaged firing pin tip. Post 64 Model 70 Winchesters have always had a tendency to blank primers because the firing pin tip diameter was too large. Usually it worked OK but if a primer had a slightly weak cup it would blank. Occasionally, gas escaping through the primer would blow the firing pin back and compress the spring, damaging it. Subsequently, the spring lack sufficient strength to hold the firing pin forward and the blanking problem got worse.
An occasional cure has been to replace the striker spring with a slightly heavier one. This can help but only if the lighter spring was a major contributor to the problem in the first place. Light weight firing pins may exacerbate blanking since they lack inertia to support the cup. This is why most light pins are accompanied by a heavier spring.
Blown primers though come via excessive pressure, soft brass, or a combination of the two. Many of the WSM's are loaded hot enough that it doesn't take much of a variation to put them over the top.
 
If I had to guess (and I do) I would guess that this barrel is a bit tight. This will certainly boost pressures.
 
The bolt face and firing pin tip will be damaged each time. Escaping gases in sufficient volume can blow the action up and be a danger to the shooter and those close.
 
altak5 said:
I have purchased a used Savage weather warrior in 270 wsm, while working up loads for it I experienced high velocities at below Max charges including blown primers. I test fired a round of Nosler factory accubond 140grain, this went 250 fps faster than stated velocity and also blew the primer out.

I am assuming this is why the gun was sold, but don't want to make any accusations.
I have purchased a box of low end Federal 130's but haven't had time to test fire one yet.
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Yep, with my ATRS Modern Hunter (.308). Nosler match 168gr would blow primers 6 out of 10 shots. I don't use that stuff in this rifle anymore.
 
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