pressure sign discusssion
What do folks use to determine the upper limit of pressure you are willing to load to? Hmm...the reloading books, of course...some say to load no higher than what the book says no matter what. Just as many say the max in reloading books are well below max for liability, etc., reasons. One conversation I had recently with a Hodgdon rep said that their max loads are at 97% of SAAMI average max pressure and that the handloader might get a bit more out of a given load than the book shows, fyi.
I watch my primer for cratering and flattening and the case head for ejector pin marks. A question is, given the batch of brass (hard or soft, etc.) and the rifle/caliber you have, how much can you depend on ejector pin marks as signs of high pressure? Some folks I've talked to say that unless you see the lettering on the case head start to get moved/smudge/whatever or get an obvious shiny mark, you're OK. Others say you shouldn't see the slightest of case head marks...ever...even if there isn't a shiny portion to the mark. Where is the pressure "line" that you shouldn't cross? For me, I've been using the "shiny mark" as the highest and I'll find a load somewhere below considering the amount of primer cratering and flattening as well. What do other folks do?
I've also heard guys say that in the bigger cases, say a 300 RUM, a slight ejector pin mark where the brass isn't flowing (i.e. apparently not moving/smudging/disfiguring lettering on the casehead or leaving an obvious shiny mark)is OK as those big calibers "do that". However, he said that in a smaller cartridge like with a .308 Winchester, you shouldn't see any ejector pin marks. ???? So can various degrees of ejector pin marks mean different things in different calibers in general? Hmmm...not sure about that.
Then you can start talking about primer pockets loosening up. And that every gun is different...
Then there are the guys who are all set up to measure actual pressure when firing the rifle--this would seem to be the safest. But most of us don't have this equipment so what do do in it's stead?
Let's hear from the guys that have been reloading and experimenting with wildcats longer than I've been alive that don't use pressure testing equipment or that can compare what pressure testing equipment says to the observations of primers and case heads after firing. What signs do they look for that indicate pressure is too high and what are the driving principles behind their decisions concerning the look of the primer and the look of the case head?
I'm just curious to see what other folks do and what drives their decisions.
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