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Re: pressure signs

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30 June 2004, 04:08
denton
Re: pressure signs
Hey Hot Core, use your PRE method and tell us how many peak PSI some of your loads are generating. You claim to have a calibrated, repeatable system, and such a system will easily give you the answer. Why do you keep us waiting?

Hot Core = no facts, no figures, no physics, just an opinion based on an opinion he read somewhere. Invited to take part in an experiment to determine the repeatability of PRE and CHE, he ran like a scalded cat. The results are in, he doesn't like them, so he has nothing but sneers for the people who rolled up their sleeves and did the work needed to gain direct knowledge.
30 June 2004, 00:44
Hot Core
Quote:

Denton,
We can't ask HC for the pressure in psi, if we can't find a use for psi relative to the real limit, primers falling out....



Hey Clark, For some reason denton is fixated on "psi". Perhaps it is because he just doesn't understand how TOTALLY WORTHLESS the HSGSs really are. It simply appears that he dosen't have the cognative ability to think his way through the myriad of problems associated with them.

The interesting thing about his continuing to ask me about "psi" values is that before I realized he is unable to understand, I explained it clearly to him quite a few times. No need to go over it again since he is obviously unable to grasp the completely excellent concepts of CHE and PRE.

HSGS = Reloaders Pyrite(Fool's Gold)!!!
30 June 2004, 07:21
Clark
Quote:

It simply appears that he [Denton] dosen't have the cognative ability to think his way through the myriad of problems associated with them.





My guess is that he could beat either of us in an IQ test and deserves lots of respect for the effort of his posts. He is just not accepting something, we are assuming something, etc.



I DO KNOW that I stand a better chance of learning something in chart form, such as when AC calculated brass failure in chamber psi, or when Denton made his chart of accuracy of measuring method.



I consider myself an advanced handloader, but I am like a blind man examining an elephant, I only know how to do my load work up system.



I would like to get a map of the pros and cons of the options before say definitively that I don't need to mess with micrometers or strain gages.
29 June 2004, 19:38
Clark
Denton,

We can't ask HC for the pressure in psi, if we can't find a use for psi relative to the real limit, primers falling out.



He may be able to develop a load with higher velocities without the primers falling out, using his micrometer, than someone else can with a psi measuring system.



We just have not figured that out yet, to my knowledge.



And if you take SAAMI as a given, he will beat you every time, except maybe with the .270 or 454.





With the strong bolt action and Mauser case head, the primer pocket growing is the real limit for me.





That is not the real limit for beginning handloaders or factory loads. For them, SAAMI is a given.



Here is my anecdote:



==============================

For my VZ24 I have a quantity of Win 257 Roberts +P brass prepped as carefully as I can, fire formed, and the primer pocket is so loose, it will not hold a CCI or Win primerFrowner



Or if I fire form with 10 gr. Unique and Cream of Wheat, and then load too hot with bullets:



257RAI 75 gr. Vmax .257 bullets that I had moly coated.



1) 49.4 gr. of IMR4895 gives 3942 fps and the extractor cut grows .0035"

The primer is loose and the brass is no good any moreFrowner



2) 48.3 gr. gives 3757 fps and the extractor groove grows .0005"



3) 47.2 gr. gives 3736 fps and no extractor groove growth



===============================
30 June 2004, 08:13
Sabot
The real problem is that we are discussing BOTH deterministic and heuristic approaches to safe pressure estimation. The labs take a deterministic approach and not only measure pressure as precisely as possible, but try to fit results to mathematical models as a second check. Just good engineering.

Most reloaders use a heuristic approach....more like "rules of thumb" to infer safe, marginal, max or dangerous pressures from observations that do not involve the direct measurement of pressure, but other convenient signs.

Now, the shocker is that the deterministic approaches are only slightly better than the heuristic ones, as long as the heuristic ones are coupled with measurement of velocity. If you spend some time with your rifle with different bullet styles and weights, along with some variation in seating depth, velocities and variations thereof will tell you a LOT about how your rifle transplates charge weight, burn rate and primers into muzzle energy. Fixed combinations of components will either be slower or faster than published data and you either will or won't encounter any heuristic pressure warnings on you way to charge weights that yeild the Max velocity in a manual.
02 July 2004, 02:45
ASS_CLOWN
Denton,

Thanks for the feedback. I may have to pick one of these systems up. I lost my DA card so I am looking at ~ $150 anyway. You still need the laptop with your system, correct?

Goodluck on blowin' away the MK thread!

ASS_CLOWN