It has come to my attention that there are an awful lot of newer members nowadays. I decided to repost this article about primer cup thickness in the interest of safety. I first noticed it shared on this site back in 2008. Good article for reference. BTW - not my doing, just reposting. Reload SAFELY!!
http://www.jamescalhoon.com/primers_and_pressure.php
Primer Cup Thickness vs Pressure
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Primer Cup Thickness vs Pressure
Hold 'em & Squeeze 'em
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Re: Primer Cup Thickness vs Pressure
Good idea Skipper, with all the new one's coming into reloading. I also saved James information, back from a few years, when he came out with that information. It can be useful.
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Re: Primer Cup Thickness vs Pressure
With my custom rifle build I have clocked my pet load of 35 gr. Bergers at 4300 FPS. The bullets are jammed into the lands by 0.010 making them right on the edge of safety. Couldn't have done it without the help of this board. I might well have ended up in the hospital. Play safe.
Hold 'em & Squeeze 'em
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Re: Primer Cup Thickness vs Pressure
I have been handloading for over 20 years. I have never had an accident or problem of any kind. But I urge everyone who is loading their own to use caution. Primers can be dangerous, be careful. Do not exceed the manufacturers top listed load data. When in doubt, err on the side of caution.
"The difficulty lies not so much in developing new ideas as in escaping from old ones."
John Maynard Keynes
John Maynard Keynes
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Re: Primer Cup Thickness vs Pressure
I really got into handloading in 1968 when I returned to The World. And even now after over 55 years and loading for over 30 calibers, rifle, pistol, revolver and shotgun, I still refer to the factory manuals when starting with a new caliber. Why take a chance with something like 50,000+ psi of pressure inches from your face and hands?
I also consider primer cup thickness for high intensity rounds like the 204R, and low intensity rounds such as the K-Hornet. There is no "one size fits all" here. If we pay attention, we keep all our fingers, and get to see out of both eyes. It's simple really, but one must pay attention if you want accuracy, and all your body parts intact too.
My loading bench recently. Out of sight is my library of loading manuals, one for every bullet and powder supplier, but trust me, they're there alright, ready for instant reference.
Having many loading manuals is good, but the fact remains one must actually read them!
I also consider primer cup thickness for high intensity rounds like the 204R, and low intensity rounds such as the K-Hornet. There is no "one size fits all" here. If we pay attention, we keep all our fingers, and get to see out of both eyes. It's simple really, but one must pay attention if you want accuracy, and all your body parts intact too.
My loading bench recently. Out of sight is my library of loading manuals, one for every bullet and powder supplier, but trust me, they're there alright, ready for instant reference.
Having many loading manuals is good, but the fact remains one must actually read them!
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Re: Primer Cup Thickness vs Pressure
Rick you bring up a good point. How many manuals do all of you have? I have 10 presently.
"The difficulty lies not so much in developing new ideas as in escaping from old ones."
John Maynard Keynes
John Maynard Keynes
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Re: Primer Cup Thickness vs Pressure
If you count the various reloading manuals, even some of the old Wildcat Cartridge books Wolfe Pub put out in the 60's, plus may company manuals i.e. Speer, Hornady, etc, Kindler and the Hornady annual reloading manual/magazine, I have over 20 that I check pretty darn regularly.
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Re: Primer Cup Thickness vs Pressure
Well Bill, didn't actually count, but it's like your stash, over 20, most likely more, as I like you, have many from the late 60's and early 70's, plus the annual manuals that the powder makers publish also. As you mentioned, Wolfe Publishing had good load info in Handloader and Rifle Magazines too. If I really had time to dig them all out and count them, I'm sure it would be something like 40 or 50 reference sources.Bill K wrote: ↑Thu Oct 12, 2023 8:25 amIf you count the various reloading manuals, even some of the old Wildcat Cartridge books Wolfe Pub put out in the 60's, plus may company manuals i.e. Speer, Hornady, etc, Kindler and the Hornady annual reloading manual/magazine, I have over 20 that I check pretty darn regularly.
Maybe this is one reason my gun room is so crowded, that it seems like the walls are closing in!
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Re: Primer Cup Thickness vs Pressure
I am sure i have more also RIck. I did not count the load info in my Handloader/Rifle magazines and a few other publications. Old timers like us seem to have a whole shelf/cabinet full of load data, plus with our PC's access to many more on the data sites, like Hornady Load Data, etc. etc.
And they are all useful and I enjoy them, as you and others do also.
I even have a couple load manuals that date back into the 40's ( Old Western/Winchester/Dupont) and I believe the first hard copy Speer but out in and around the early 50's.
And they are all useful and I enjoy them, as you and others do also.
I even have a couple load manuals that date back into the 40's ( Old Western/Winchester/Dupont) and I believe the first hard copy Speer but out in and around the early 50's.
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Re: Primer Cup Thickness vs Pressure
Is it just me that wonders where everyone are ? It seems to me that here, over the last few weeks/months, only four us are posting.
Skipper, Tom, Rick and myself. Come on folks there has to be more hanging on.
Skipper, Tom, Rick and myself. Come on folks there has to be more hanging on.