Sticky for pressure signs?

B

Bustercluck

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Why isn’t there a sticky for analyzing pressure signs? This is probably the bigggest concern I hear from new reloaders “I just hope I don’t blow myself up”. I’m sure it’s been discussed on here lots, but a thread with lots of pics and discussion would probably help alot.
 
Part of it may be that those new to reloading should be doing so with a new firearm of new construction and keep to the listed values in a reloading book. Plus, reloading books have that information in them and sometimes there are just things that people shouldn't up and go do from Internet advice. Once someone gets experience from a reloading manual they usually have some common sense to critique what they read on reloading on the Internet, search old threads, and go from there.

The best advice has always been get a reloading book and stick to it, read and see the information on over pressure signs in it, and maybe people don't want to circumvent the best advice until they 'graduate' from that advice?
 
I measure the case web just above the extractor groove. When I see expansion here I know I am approaching the material limit of the brass.

No pierced primers, stuck cases or heavy bolt lift... So long as I remember to bring calipers to the shooting bench (yes micrometer can be more precise)

Just stop when I see .001" growth at the web.

Took me 25yrs to figure this out, and seldom do I see this trick discussed. 🤷‍♂️
 
B said:
If we do end up with a sticky, can we have another for casting chicken bones? Or reading tea leaves? "Reading" pressure signs as a way of loading is about as accurate. There are many, many instances where the only sign you will get is a part breaking or the gun failing in a serious way.
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What kind of parts have ypu broken or catastrophic failures from too much pressure? Are you shooting pistols? Or semis?
 
Hand Skills said:
I measure the case web just above the extractor groove. When I see expansion here I know I am approaching the material limit of the brass.

No pierced primers, stuck cases or heavy bolt lift... So long as I remember to bring calipers to the shooting bench (yes micrometer can be more precise)

Just stop when I see .001" growth at the web.

Took me 25yrs to figure this out, and seldom do I see this trick discussed. 🤷‍♂️
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I think I have this going on right now and I’m going to measure some new cases against fired and then measure the new ones again after I fire them. All other signs are fine, but the primary extract is a tad tight.
 
Bustercluck said:
What kind of parts have ypu broken or catastrophic failures from too much pressure? Are you shooting pistols? Or semis?
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Yes, personally I have had issues with manufacturer data being wildly overpressure. I was impressed the the incredible report of my 10mm loads but not impressed with losing slide stops and extractors. Then Hodgdon lowered the "max" of the load id been using by nearly 2 grains. The difference was 37,000psi vs the 50,000 of the older load. I haven't had any issues at all with the new data.

The only way for me to know if their max was safe for my guns was to "read" the brass, track the increases in velocity, and monitor ejection and reliability. A bolt gun is easier to "read" but it is still not a reliable indication of much unless you are the gambling type. Stick to manuals and investigate if you find stuff that doesn't make sense.

FWIW it is "funny" how Hodgdon changed that load after I emailed asking them why it seemed so hard on guns and why both QL and GRT pegged it at 50k PSI. Pulling over 3500 rounds was not fun. It's ok to question the manufacturers. Don't be scared to.
 
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If you cannot learn about pressure signs without a sticky then maybe reloading isn't for you...

Reloading should involve a lot of reading/studying BEFORE you ever touch a press. If you haven't learned anything about pressure signs yet, read another reloading manual. I know my Speer manual certainly discusses some signs of over-pressure.
 
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B said:
Yes, personally I have had issues with manufacturer data being wildly overpressure. I was impressed the the incredible report of my 10mm loads but not impressed with losing slide stops and extractors. Then Hodgdon lowered the "max" of the load id been using by nearly 2 grains. The difference was 37,000psi vs the 50,000 of the older load.

I haven't lost a part since. A bolt gun is easier to "read" but it is still not a reliable indication of much unless you are the gambling type. Stick to manuals and investigate if you find stuff that doesn't make sense.

FWIW it is "funny" how Hodgdon changed that load after I emailed asking them why it seemed so hard on guns and why both QL and GRT pegged it at 50k PSI. Pulling over 3500 rounds was not fun. It's ok to question the manufacturers. Don't be scared to.
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So we should trust reloading manuals? Or don’t trust reloading manuals? I’m getting mixed messages here…
 
Bustercluck said:
So we should trust reloading manuals? Or don’t trust reloading manuals? I’m getting mixed messages here…
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In general you can trust them. That said, typos DO happen, and it never hurts to cross-reference between multiple manuals or sources. I only have the one hardcopy manual, but I also use various online sources such as Nosler and Hodgdon.
 
Hand Skills said:
I measure the case web just above the extractor groove. When I see expansion here I know I am approaching the material limit of the brass.

No pierced primers, stuck cases or heavy bolt lift... So long as I remember to bring calipers to the shooting bench (yes micrometer can be more precise)

Just stop when I see .001" growth at the web.

Took me 25yrs to figure this out, and seldom do I see this trick discussed. 🤷‍♂️
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Have you tried this method with rimmed brass like 45-70? Or something belted like the 300win mag? I wonder how they would react?
 
Speer did some older manuals without pressure gear on some cartridges, just used base expansion measurements. Ed Matunas, the chief eng at Speer at the time, wrote an article about it and admitted it was a mistake to do it that way. When they ran the same tests with pressure equipt later on, they were as much as 10,000+ psi out on their "pressure", for data that had been published.
There are some references to that article around the net, forget who published it, published in early 90's I believe, manuals were back in 80's. Ed Matunas's name will be in them in the credits.
Primal Rights has some of the best pics of pressure issues, and a half decent article on it.
 
Bustercluck said:
13 comments in and there’s four wildly different opinions. But there’s no need for discussion?
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There is absolutely a need for discussion, and it is happening right now, but that wasn't your original request: a sticky for new reloaders was.

A sticky in regards to newbies doing something should be more of a 'definitive' answer: like using a torque wrench to install tire lug nuts to the manufacturer's stated spec. It doesn't work if, as you say, if there is '13 comments in and there's four wildly different opinions'. All a newbie is going to do is ask who's right, which will increase the debate.

I will cede if I am wrong, but 'stickies' should be for mutually agreed upon answers, not debates.
 
Aniest said:
There is absolutely a need for discussion, and it is happening right now, but that wasn't your original request: a sticky for new reloaders was.

A sticky in regards to newbies doing something should be more of a 'definitive' answer: like using a torque wrench to install tire lug nuts to the manufacturer's stated spec. It doesn't work if, as you say, if there is '13 comments in and there's four wildly different opinions'. All a newbie is going to do is ask who's right, which will increase the debate.

I will cede if I am wrong, but 'stickies' should be for mutually agreed upon answers, not debates.
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So once again we have another comment that has nothing to do with pressure signs, but all to do with virtue. There’s only one person who actually commented on a sign of how they identify pressure issues.

I’ll put the challenge out to the posters above to put together their foolproof plan for newbies that doesn’t have any controversy, mistakes and combines all of the necessary information anyone would need.
 
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