How do I find the first stages of pressure signs and how many gains should I back off once I reach it ?
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Edited: Mar 10, 2020
Pressure signs on Magnum cartridges
Pressure signs on Magnum cartridges
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On my belted mags, I always watched the primers closely. As they start losing the round edges, I make my increases in smaller increments. Then I start watching for catered or busted primers, stiff bolt lift and/or tight extraction. Of course always measure the brass too.
The new problem I've ran into is using RL17 in my .375 Ruger. I've tested loads to well passed book listed max and have no pressure signs at all. Others have found the same issue with RL17 in the .375 Ruger.
That said, RL17 was the magic number for the .375 Ruger. I'm matching .375 Wby speeds with a 23" barrel. 300gr @ 2700
Begin by adjusting your sizing die in such a way that the case headspaces not on the belt but between the shoulder of the chamber and bolt face. You find the bolt closing with very slight resistance on the sized case. This will prevent a lot of premature case head separations. For excess pressure signs, I Like to use, like most others, a combination of difficult extraction, excessive primer flattening ( make sure it is not due to excess head space), extractor plunger imprint on the case head, primer pocket expansion, measuring the web expansion and signs of case head separation ( visible by the squiggly shiny line above your case head in the webbing) or easy to spot with a flashlight or the straightened paper clip scratch and feel method inside the case. Remember that the softness grade of the brass is important to signs like plunger marks on the case head and primer pocket expansion. Imho that possibly could mean that one hot load is fine in one case lot, but may be not in another. Therefore use always imho more then one method . Let me know if I am wrong, I like to learn.
Oh man you’ve got it figured all out. I never loaded any belted magnum piece of brass more than twice for this reason, as it was my dads very expensive gun haha. Just check that spot with the pick/honed popper clip trick as you keep loading after using the collet and I don’t see you running into any major issues.
I just measured the case just above the belt. (7mm Rem Mag) it reads .5125” and if I’m correct it should be at .511” before it should be sized down with larrywills collet die. Now it does chamber after bumping the shoulder back .001“ -.002” but after firing it has a slight resistance when lifting the bolt(More than usual). I thought that shouldn’t happen if I am bumping the shoulder back every firing. But maybe it is just above the belt that’s the issue. I have the collet die and a better press coming in Thursday so hopefully this is true and solves this issue because I didn’t see any visible pressure signs other than maybe minor ejector swipe which isn’t always a real sign of excessive pressure so then shouldn’t call for a hard bolt lift without seeing any real viable signs. Thanks for the input though. Always appreciated and interesting getting other people’s perspectives on any reloading issues, or practices.
Too vague of a question. The answer varies by cartridge type as well as cartridge. Just enough info for one type could blow you up if extrapolated to another. Rimless pistol, rimmed, bottleneck rifle, belted magnum? The answer/available signs to use change by platform, too.