reading pressure signs

[Koda]

My last range session I experienced some pressure signs, stiff bolt lift, case head crack and extractor impression. These were only on the loads I set back deeper to test so I wont do that again, plus I learned my rifle likes the bullet closest to the lands anyways. And it was random, other cartridge loads in the same set with the same setback were fine.
I was told somewhere that as brass is fired it hardens and thus shortens its life. Whats odd is I did not experience these pressure signs with the very same load recipe and bullet setback test until the 3rd time reusing the brass. I'm wondering if this is because of the brass hardening from use and becoming brittle or if Ive exceeded maximum charge and/or setback? I could back off on my powder charge weight except I'm not experiencing these pressure signs with the loads closest to the lands. Does annealing the brass before reloading it extend its life or are the pressure signs a symptom of overcharging or over seating or some other improper reloading technique?

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[Certaindeaf]

All three issues may well be due to the case head separations caused by resizing to saami specs and compounded by a generous chamber. How are you sizing your brass?

 

[Koda]

All three issues may well be due to the case head separations due to resizing to sammi specs. How are you sizing your brass?

Im using a full length sizing die but backed off to minimal shoulder bump, enough so the case chambers and extracts freely.

 

[daved20319]

Need some more detail, Koda. Rifle, cartridge, powder type and charge, brass brand and how many times fired, primer type and brand, reloading dies (small base?), bullet brand/type/weight. What/who's load data are you using? Are you running max or near max charge weights? Was that last session significantly warmer or cooler than before? How did you determine your headspace, and have you established the max COAL in your rifle with the particular bullet you're using? What is your seating depth, and is it significantly shorter than the book data? Going longer isn't typically an issue, as long as you're not jamming the bullet in the lands. That's just off the top of my head, I know I'm leaving something out.

Yes, brass does work harden with shooting and resizing, and annealing can help, but doing it right is an expensive proposition, and one that's probably not worth the cost if you're loading for a common cartridge, or just shooting for your own entertainment. I have buckets of .223, most of it range pickup, if it looks questionable I toss it. Definitely not worth the cost of an annealing setup. Max charges will accelerate the work hardening, as will a "loose" chamber vs. a tight resizing die. And any combo of the above and more can all contribute. But answer some of the questions above and maybe we can help you figure out some answers. BTW, "bullet setback" is a term usually applied to handguns, and refers to cartridges getting shorter due to recoil. What you mean is seating depth, not trying to be nit picky, but sometimes terminology matters . Later.

Dave

 

[Stomper]

This was a pretty decent annealing set up that I acquired for under $300, And it worked flawlessly through that entire hopper of 556 brass in the video I posted.

Annealeez – For a Hot Piece of Brass!

annealeez.com

 

[po18guy]

How hot was it when these anomalies occurred? Pressure rises with temperature. Sadly, there is no cartridge pressure warning on the dashboard of our guns.

 

[tac]

Time for a reminder that SAAMI and CIP are NOT identical sets of specifications.

SAAMI figures are advisory only, and intended to be used by American manufacturers.

CIP figures are compulsory and compliance is legally-enforced by rigorous and compulsory testing and spot-check evaluation of guns, ammunition and
components thereof.

 

[arrowshooter]

Annealing is only for the neck/shoulder of the brass so it will not help what I see in your photo. What I do see is most likely pressure related to continual shooting at a higher pressure. This probably is the outcome of seating deeper and not running a new ladder to keep from blowing stuff up like that. If you never had this issue with the longer COAL then you are good, just make sure that you are not pancaking the primers.

 

[TTSX]

Wait until you pierce a primer. That's a unique smell, for sure

 

[tac]

Sir, you wrote - 'My last range session I experienced some pressure signs, stiff bolt lift, case head crack and extractor impression.'

Each one of those three things was an angel tapping you on the shoulder saying 'uh-oh....'

And then you wrote - 'These were only on the loads I set back deeper to test so I wont do that again.'

That's certainly one of your better decisions. I'd like to think that you'd keep to it.

 

[thorborg]

That's definitely a dangerous issue to be resolved.
Splits and cracks on the other end, while bothersome, are not likely to be a safety issue but definitely beware on on the head end.
Annealing is not the issue.
Methinks you should look to the short shoulder, and a close examination of reloading practices to resolve this.
A short shoulder under full power violently fireforms and stretches' the brass, much material coming from the web area thinning it as everything moves forward to fill the gap ,
The split did not necessarily happen at the time it was stretched, once thinned, it could have been a ticking time bomb for future reloads loads regardless of now proper resizing.
Without testing time and equipment to measure the wall thickness near the web of each and every round, myself would now be suspect of my brass.

 

[Koda]

Annealing is not the issue.

thank you. This is what I was looking for.
What is a " short shoulder"? Im using a full length sizing die backed off until I get minimal shoulder bump, enough so the resized case chambers easy and smooth.

It seems to me if its not an annealing issue then rifle brass is only good for 2 or 3 reloads. This brand Im using I probably will limit to only 2 firings....

 

[Koda]

Annealing is only for the neck/shoulder of the brass so it will not help what I see in your photo. What I do see is most likely pressure related to continual shooting at a higher pressure. This probably is the outcome of seating deeper and not running a new ladder to keep from blowing stuff up like that. If you never had this issue with the longer COAL then you are good, just make sure that you are not pancaking the primers.

Thank you for this, this is what I was looking for. Your right... I didnt do another ladder for the different seating depths.. I wont do that again. that makes sense now, thank you for pointing this out.
I did work my way up the different seating depths but what decieved me is the first rounds in the deeper seating string didnt show pressure signs so I continued but then I got one...

 

[Koda]

How hot was it when these anomalies occurred? Pressure rises with temperature. Sadly, there is no cartridge pressure warning on the dashboard of our guns.

it wasnt a terribly hot day that day, I lucked out as it was a rare day was kinda overcast in the morning and took longer to burn off, plus I was in shade.

 

[Koda]

Need some more detail, Koda. Rifle, cartridge, powder type and charge, brass brand and how many times fired, primer type and brand, reloading dies (small base?), bullet brand/type/weight. What/who's load data are you using? Are you running max or near max charge weights? Was that last session significantly warmer or cooler than before? How did you determine your headspace, and have you established the max COAL in your rifle with the particular bullet you're using? What is your seating depth, and is it significantly shorter than the book data? Going longer isn't typically an issue, as long as you're not jamming the bullet in the lands. That's just off the top of my head, I know I'm leaving something out.

Rem 700 in 25-06. Nosler brass 2x fired prior, IMR 4831 52.5gr, Federal 210 primer, Redding FL sizing die, Nosler 120gr partition.... Im on the higher end of charge weights but not max. I use a Hornady gauge to determine max COAL from the lands using the same bullet from the ogive. I did a "round robin" test with 6 rds each starting at -.005" from the lands in .005" increments to -.020" seating depth. I only experienced pressure signs in the -.015 and -.020 sets (but not every shot so was deceiving me...). This is actually my second seating depth test but the first on I didnt have a stable bench to check accuracy, was a very hot day the first one and recall one stiff bolt then but attributed it to random... wont do that again.

 

[Koda]

So based on the replies from the more experienced reloaders here's my summary...
I'm on the upper pressure end of my "recipe", I can safely seat the bullet up to no more than -010" max from the lands with this powder charge, and probably limit my brass to only 2 firings before discarding them.
What I might do is reduce my powder charge by 1 or 2/10th a grain and check my velocity, but will probably continue to seat the bullet closer to the lands because all my groupings got better the closer to the lands. -.005 seating depth was 1moa with no pressure signs in that string of fire.

 

[Greenbug]

You may be below the max powder charge in your reloading manual, but it sounds like you are at or over max charge for your particular rifle and component package.

All guns are different, we need to heed the warning signs and remain safe!

 

[daved20319]

Rem 700 in 25-06. Nosler brass 2x fired prior, IMR 4831 52.5gr, Federal 210 primer, Redding FL sizing die, Nosler 120gr partition.... Im on the higher end of charge weights but not max. I use a Hornady gauge to determine max COAL from the lands using the same bullet from the ogive. I did a "round robin" test with 6 rds each starting at -.005" from the lands in .005" increments to -.020" seating depth. I only experienced pressure signs in the -.015 and -.020 sets (but not every shot so was deceiving me...). This is actually my second seating depth test but the first on I didnt have a stable bench to check accuracy, was a very hot day the first one and recall one stiff bolt then but attributed it to random... wont do that again.

Based on Nosler load data, you're over max by 2.5 gr. with that powder/bullet combo. Hodgdon's show's 53 gr. as max, but with a different bullet. Nosler's COAL is 3.2", you said how far off the lands you're running, but didn't actually include your COAL.

IMO, I'd say you're over max period, but definitely for your rifle with that combination of components. If it was me, I'd start over with the Nosler data, using their COAL, find the best charge for your rifle, then tweak seating depth. Alternatively, as you already know your rifle likes to have bullets close to the lands, start at .010" off the lands, but still using the Nosler charge data to determine best charge weight. Hope that helps.

Dave

 

[Koda]

Based on Nosler load data, you're over max by 2.5 gr. with that powder/bullet combo. Hodgdon's show's 53 gr. as max, but with a different bullet. Nosler's COAL is 3.2", you said how far off the lands you're running, but didn't actually include your COAL.

yes, for Nosler data. This has been the confusing part of learning to reload... different load data show different values. My Lee Modern Reloading book says 53gr is max... I worked my way up at the beginning and say no pressure signs, but those were with once fired or new brass. What load data to trust is confusing....

I check my COAL with a gauge from the ogive and seat my bullet dept from my rifles lands. Its my understanding that measuring from the bullet tip is not accurate at all despite SAAMI specs? Correct me if Im wrong.

 

[Koda]

You may be below the max powder charge in your reloading manual, but it sounds like you are at or over max charge for your particular rifle and component package.

All guns are different, we need to heed the warning signs and remain safe!

agree, Thats why Im asking here. I think Im at or near the max for my load recipe. See my summary I posted above... I might reduce my powder charge a tiny bit and start over...