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The two best indicators of high pressure are hard bolt lift/sticky extraction and any sign of brass flowing into extractor cuts or ejector pin holes. Primers vary with hardness so their appearance is not consistant. Miking case heads is ok for those with experience with good mikes but "ANY" brass flowing toward the unsupported parts of the bolt face is a sure sign you are too hot.
 

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I disagree on the rifle flying apart because pressures are so high at the sight of a little brass flowing. Slight brass flowing means generally you are at the 65,000 psi threshold most cartridge brass starts to flow. To load the hottest practical ammo reach this point and back off two grains. This is a practical maximum for that rifle. The chronographs are helpful but the load manuals are not loading in your rifle so you have to do the footwork. Incidently brass is the weakpoint, most rifle actions will handle more pressure than the brass can so it is the weak link.
 

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Well yeah the lever actions are not in this play. But the fact is if there is no brass deformation in a strong bolt action along with easy extraction the load is safe. This works in fact and all rifles are not the same. I have never blown a primer and most often cratered primers are the result of loose fitting firing pins or bolt face roughness. Seldom is it that I end up more than 2 grains from handbook maximums anyway and generally go with the most accurate load. I have witnessed many factory loads that showed noticable brass flow though not dangerously so.
 

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Loader, my 30-06 gets 2850 fps with a 180 grain Speer spitzer on top of 59 grains of H4831 using a CCI 250primer. Cases easily last ten firings, I get fine accuracy and smooth extraction. Seems your working at it backwards by picking an absolute velocity and calling that the pressure level that is safe. Simply put there are rifles out there that could show high pressure when pushing a 165 grain bullet at 2800 fps. That is almost like picking a point in outer space and shooting for it. Nothing replaces working up loads in individual rifles.
 

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Loader I believe we agree on this issue. There is something to different brands of brass showing flow (any distortion of case head) due to one brand being softer than the other before the even mild pressure of 52,000 psi. In this case I back off till it stops and call this max for the brass. Actually I now work up from below any time I change brass. Years ago I had some Federal brass that was far softer and 25 grains lighter than the Remington brass I worked the load up for show dramatic high spots where the ejector pin hole matched up. I am now a firm believer in working up any load where all components are not matched exactly. In my opinion the cartridge case is the single greatest factor in pressure deviation with the bullet being second.
 
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