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Posted: 10/27/2014 3:22:06 PM EDT
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Has anyone done a study on which LRP have harder cups than others? I'm making up some 308 loads to shoot out to 400 yards and as I approach the IMR listed max my primers are really flat with some cratering too. I had been using BR2 primers which I know are softer than most,so I loaded up some with standard CCI 200's as well. ( that was all I had on hand )
Are Federal std LRP or Gold Match harder that CCI200's? How about Remington? |
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Don't know about hardness, but there is a chart of thickness. I assume they are all made of
the same material, so thicker should be less prone to early pressure signs. That said, if you are pushing the pressure boundary if may be wiser to just stop at an accurate load instead of pushing it. Link |
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Quoted:
Happen to be loading in LC brass? Quoted:
Quoted:
I'm not seeing any other pressure signs on the brass just the primers and I'm 1.6 grains from max. Happen to be loading in LC brass? It is more than just LC brass, I bought some cheap Perfecta 308 ammo and the brass is heavier than Win brass but it is actually more consistent than Win by weight. It did have crimped primers but it wasn't labelled 7.62 x 51 |
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Quoted:
Happen to be loading in LC brass? Quoted:
Quoted:
I'm not seeing any other pressure signs on the brass just the primers and I'm 1.6 grains from max. Happen to be loading in LC brass? I did my work up with Remington and Hornady. I have some 1X Black hills that I want to load too. |
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Winchester primers are supposed to be hard. Have you tried the CCI military primers (#35??) I used some a few years ago for my M1A and M1 Garand. Didn't push max. loads, but they worked fine. I'll try some Win primers. I've used them before on SRP. Aren't the #35 primers equal to a magnum? |
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Let us clue into some reloading basics.
#1 A load worked up in one brand of rifle brass is not necessarily going to safe, let alone accurate or reliable in another. God's Fact! #2 Swapping primers with the idea of changing pressure signs is off the wall! Powder charge and internal case volume are going to be main factors with pressure! #3 If you change a component you rework up the load! #4 Follow established reloading practices and be safe for God's sake! The hardest primer is going to the CCI #34 Large Rifle Mil Spec. the equivalent to the CCI 250 Large Rifle Magnum primer. |
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http://www.accuratereloading.com/primer.html
http://riflemansjournal.blogspot.com/2009/06/primers-large-rifle-primer-study.html http://precisionrifleblog.com/2012/07/02/most-accurate-rifle-primers-for-precision-reloading/ http://www.sksboards.com/smf/index.php?topic=56422.0 Just some nightstand reading..... Hope you find something in there you didn't already know. If I were to throw my $.02 in... I wouldn't worry all that much about cup hardness, unless you are just using the term like a catch-all for sensitivity or something along the lines of activation energy. Most of the cup dimensions are fairly similar and by the time they draw that cup, there is a fair chance that the cold working changes the radius area where people tend to "look" for plastic flow as a sign of pressure. It is entirely possible that those differences could be over-interpreted. I am still in the habit of looking at that spot on a regular basis, but I rely on strain gages to tell me what the load is doing in terms of kPSI. If you are going to play with the hot end of things, be sure to consider getting into measuring with a strain gage and always watch the temperature. Running at or into the red zone isn't worth it in my experience, but to each their own. |
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I'm not seeing any other pressure signs on the brass just the primers and I'm 1.6 grains from max. 1.6 grains "over max" or "under" and you think it's a primer hardness problem? Who's data are you using? There exists a wide range of data depending on who's you use. I always use the bullet manufacturer's over any other source. |
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How much "heavier than Winchester" is your brass? Empty, resized, trimmed and unprimed Lake City averages 179 grains. If your brass is anywhere close to that weight you need to be closer to 2.0 grains below the maximums listed for commercial brass cases. Never more. That means you need to reduce your powder charge by 3.6 grains. It is not a mystery why you are having issues.
Federal 210 M (match) primers are known to be more sensitive than other brands and should not be used in semi-autos. Winchester's are tough, and so are CCI #34. If you are getting primer issues AND you are 1.6 grains over the data you are referencing, then you need to lower your powder charge. I say at least 1.0 grains, maybe more. Please post your load specifics: Empty unprimed case, weight and brand. Powder type and charge weight. Bullet brand, weight and model. OAL seating depth. Primer. |
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