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Primer pockets opening up and ejector pin stuck in bolt face.

last time out shooting I had a problem with several reloaded cartridges. The primer pockets actually opened up enough that when I ejected the spent round the primer fell out and came out loose from cartridge. After examining the bolt I noticed the ejector pin was crammed into the bolt face and stuck there. The pin did not stick until the last shot fired, which was about the third case where the primer came loose. For the past 8- 10 months have been neck sizing only...after 3-4 reloads the bolt became a little stiff to close so I bought a redding body die and started body sizing after each 3rd or 4th reloading to bump the shoulder a little. I'm afraid the last time I ran cases through the body die I might have bumped the shoulder too far. Does this sound like it may be causing the problem with the primer pockets and stuck ejector pin? (I'm picturing the cartridge in chamber with too many thousandths of a gap at the shoulder and when fired the whole case is "slamming" back into the bolt face.)
Looking for some help or ideas...thanks!
 
Are you getting an imprint of the ejector pin on the brass? See the bottom left of the right cartridge in this photo.

pressuresigns.gif


That is a sign of excessive pressure, along with enlarged primer pocket. You are slightly beyond the max load listed by Sierra here:

http://www.6mmbr.citymaker.com/f/Sierra308Win.pdf

A long shot, but could you have annealed the brass and got the head too hot?
 
Hey did you anneal the cases ?. i had some bad problems with some 22ppc cases i annealed, i did it just like they say to and must have messed up.primes were falling out and stuck in the pin hole,i had to scrap em and decided never to try that again.
 
jsteiger said:
last time out shooting I had a problem with several reloaded cartridges. The primer pockets actually opened up enough that when I ejected the spent round the primer fell out and came out loose from cartridge. After examining the bolt I noticed the ejector pin was crammed into the bolt face and stuck there. The pin did not stick until the last shot fired, which was about the third case where the primer came loose. For the past 8- 10 months have been neck sizing only...after 3-4 reloads the bolt became a little stiff to close so I bought a redding body die and started body sizing after each 3rd or 4th reloading to bump the shoulder a little. I'm afraid the last time I ran cases through the body die I might have bumped the shoulder too far. Does this sound like it may be causing the problem with the primer pockets and stuck ejector pin? (I'm picturing the cartridge in chamber with too many thousandths of a gap at the shoulder and when fired the whole case is "slamming" back into the bolt face.)
Looking for some help or ideas...thanks!

Savage???? My G/Fs Savage will not handle what my model 70 will. "Warm" loads in my model 70 .243 will stick the bolt, blow the primers and break the ejector in the Savage. The Savage is a decent shooter and it was pretty much free or I would have sent it down the road.........
 
I have never annealed the cases. I think they come from Lapua already annealed. RonAKA you are right about the mark on case face. quite a bit of my brass has that shiny mark from the ejector pin. I have seen that before but never paid much attention to it because gun was shooting so well. But it is there on quite a bit of my brass. Also didn't realize I was at the end of the max load for Benchmark at 42 gr. I honestly didn't even think I was close. So you think this could be the cause of the stuck ejector pin? Seems like you could be right on about the over expanded primer pockets.
 
If you have not annealed then that should not be an issue.

I believe the photo I posted was intended to illustrate high but somewhat acceptable over pressure in the right image. I have a fair number of cases that look like this in my hunting loads, but I have never seen any evidence of leakage around the primer.

The one on the left is very excessive over pressure. The brass has extruded back into the ejector pin hole, and when you eject the case the extruded part has to shear off. If you have had this issue to the point where you have to get the bolt repaired, then there is no doubt, pressure is too high.

Benchmark is not supposed to be temperature sensitive. Was it hot outside when shooting these loads? Just a thought.
 
Your pin is probably jammed by a bit of brass that flowed into the hole and was sheared off when you opened the bolt. Try taking a small punch and pushing in on the pin. If you can get it to move in and out even a small amount it will probably work its way out with a bit of manipulation.
And recheck your load and reloading procedures. My WAG is your cases are over max length.
That coupled with a warm load put you over the limit.
 
just wanted to say thanks for all the help guys. also have one more question...as I put more and more rounds through the gun is there anything that needs to be adjusted with my reloads to account for the natural wearing out of chamber/barrel/bolt face. I'm probably at about 1800 rounds now. Are there any normal wear issues at this stage in the life of the gun that could be combining with the fact that my load is a little too hot? I don't think that my case length was long. I don't check each and every one but I do spot check every 10-15 to make sure they're within specs. And yes it was a good 90-92 degrees the day these primer pockets opened up.
 
Blowing primers out is a HUGE sign of excessive pressure in the load. Im my pressure testing it usually happens in the 70,000+ psi range which is essentially a proof load. It won't be long before something else fails and perhaps dangerously so!

The advice to start low and work up is because rifles are different, powder lots are different and so is everything else that goes into a cartridge. However, it doesn't do much good to start low if a person ignores the signs of excessive pressure when he sees them!

Benchmark is a faster powder than I would care to use in a .308 with a 168; H4895 would be a much better choice. The quoted load is not only showing all the signs of excessive pressure, but it is over the Sierra maximum load. In all the pressure testing we do, one thing we consistently see is that Sierra's max loads are right at 60,000 psi for most modern cartridges (like the .308) and exceeding them to any degree is unwise.

I don't want to sound too much like an old scold, but excessive pressure endangers you as well as the guy shooting next to you who has the right to expect a safe day at the range. Our safety depends on each other's responsible reloading practices!
 
jsteiger: If you're concerned about throat erosion as it relates to bullet seating depth, use the Stoney Point/Hornady chamber gauge and with those measurements seat the bullets accordingly. I also use the Sinclair chamber over-all-gauge(s) and take actual chamber length dimensions and trim (or not) based on the length of my chamber, and they do vary a lot, some by as much as .040" longer than max case length. My 308 (Tikka barrel) with 1250 rounds fired is just starting to show the very slightest beginning of firecracking in the throat, as seen with my Hawkeye borescope. Kevin Thomas, formerly with Sierra Bullets/ now Lapua did an exhaustive test of 5 barrels and found they all were "toast" at anywhere from 3800 to 4100 rounds fired, but even at that continued to produce good, not great groups.
 
There is just no easy way to ask this. Why the heck, after you saw that one of your loaded rounds was so hot that it opened a primer pocket, did you keep shooting those loads? Do you think that you are immune from harm? It is very possible that a case could have let go, wrecked your rifle, and if you were not wearing high quality shooting glasses, cost you the vision in one or both eyes. You were wearing shooting glasses, weren't you? A little advice...when you see evidence of excessive pressure, stop shooting immediately, and investigate. You are smoking over an open can of gasoline.
 
I agree with Boyd 100%. After having a few chunks of steel whiz past my face from the guy next to me at the range when his rifle popped, I learned a new respect for pressure. I also nearly ruined my shorts as well.

Remember, if your rifle pops it may not be you that gets hurt, but the guy who is teaching his kid to shoot beside you, or whoever happens to be there.

If you are not checking a load manual, than you need to do so. And preferably more than one. In my opinion, the internet does not count as a manual in any way unless the info is from the powder manufacturers site. I still prefer a paper manual over anything.
 
In a little defense of the original poster, it sounds like this load has been used for some time, and the only changes were in the re-sizing methods. The load is 0.6 grains over the Sierra max, so certainly not extreme.

I also would wonder what has changed. Is Benchmark that temperature sensitive to 92 degrees?

With respect to the barrel burning out, I doubt that at 1800 rounds. A 308 should be good for at least 3000. And as the throat moves out, and seating depth remains constant, I would expect pressure to come down, not up.

I don't think there is any question that the pressure is now too high, but the question remains as to why it went up.
 
RonAKA, you are right...I have been shooting this same load for quite some time with no signs of excessive pressure. I do take my safety and those around me seriously and would never put anyone in harms way intentionally. I have tried to be very strict about my reloading regiment and consider safety top priority...I never immagined that two cartridges loaded the exact same way could fire with such drastic difference in pressure...if I thought the problem with the primers was caused by excessive pressure I never would have fired another shot of this load. I guess I assumed it was ejection/extraction malfunction, checked the bolt and all looked and functioned ok, and tried firing another round. I realize now that what I should have done is STOP right away and get someone with more experience to take a look at the problem.
BoydAllen, I do understand your question...I guess the answer is ignorance. I had no idea that excessive pressure could cause the primer pocket to open up like this. Like I said, I have never had any pressure signs in the past and had no idea that this was a dangerous situation. I'm glad I learned my lesson with nothing more than my pride a little bruised.
 
No offense, but have you ever read any books on reloading? I am just curious, as most explain the signs of overpressure. If you haven't, I recommend The ABC's of Reloading and Modern Reloading second edition. They are both excellent and provide a ton of information so you don't have to take a hit to your pride again. ;)

I also meant no offense by my other post, and I'm sorry if I offended. I forget that some people don't understand some signs of overpressure and mistake them as something else. After nearly getting my face rearranged last year I get real nervous about this stuff and probably need to chill a bit. Hope all goes well for you from here on out.
 
The intent of my post was to convince you of the seriousness of the situation and the possible consequences should you do the same thing again. It makes me happy that you have gotten my intended message. I was rough because I was worried that you might not be so lucky next time.

Once I saw a fellow at the range that was shooting a 22-250 that was showing pressure signs that seemed to make no sense, given the load that he told me that he was using. We discovered the problems. He was extremely sloppy in his powder measuring technique, and did not understand what standards he should hold, and he had an immense carbon deposit in the throat of his chamber, that took a lot of time with an abrasive cleaner to remove.

Good luck with your search for the cause of your problem. Are your cases trimmed to their proper length? If they are very much over maximum, they can be forced into the bullet as the bolt closes, and raise chamber pressure.
 
Good morning guys, absolutely no offense taken! I'm glad you guys straightened me out. I have read a reloading manual by Hornady from front to back...And I have to say you're right again, because I should have recognized this sign as a bright red flashing STOP DUMMY!!! SOMETHING'S WRONG!!!
It has been a while since I've looked at the manual and maybe need to go back and re-read it. Although this is not one of the things that should be forgotten after reading it the first time.
 
Powders are funny. When loaded in their design operating envelope, and yes powders are "designed" by formulation, the charge weight/pressure plots in very linear fashion. Some powders even have a "platue" in the the plot depending on the case volume/bullet weight/bore diameter. Some folks refer to this combination as "Optimum Charge Weight" and you had better believe the ammo companies know all about it, otherwise some specialty loads (FGM comes to mind) wouldn't shoot as well as it does on most rifles.

But if you venture past the design operating envelope powders start to get very touchy. As pressures increase the burn rate of the powder increases and can go from controlled burn to straight explosive burn. Otherwise known as the non linear operating range. If you are right at the edge of this a very minute change in anything, not just powder charge, can push things over into rapid pressure rises area of the curve.

Typically combinations of faster powders and mid weight to heavy bullets for a given cartridge are where this will show up faster.

Some short range bench resters shooting the 6 PPC tend to operate right at the edge of the curve with N133, but get away with it by way of very tight tolerances in the chamber, very strong single shot actions, best quality brass and very careful measuring of powder charges for conditions.

Best pay attention to the loading manuals, the newer ones at that. For instance the Accurate manual changed a lot of loads once they switched over to more accurate pressure measuring techniques/equipment. Likewise Sierra changed a lot of loads from older manuals to the latest, once again due to more precise pressure measuring equipment.

When right at the edge, any change, a different lot number of primers that are a little hotter, a new lot of powder that is a little faster (Varget comes to mind as do recent lots of RL-25), a new lot of bullets of slightly larger diameter, a different brand of bullets even though of the same weight, a twenty degree increase in temperature (think winter and summer loads of IMR 4064), brass with a different internal volume, whatever can get you overpressure when max-ing out a load.
 
BoydAllen said:
he had an immense carbon deposit in the throat of his chamber, that took a lot of time with an abrasive cleaner to remove.

Something seems to have changed in the original poster's setup over time. I also wondered if carbon build up could be it? Or any change in primer type?
 

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