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Quaka: I'd bet a crisp $2 bill you're way over pressure before your ammo gets hot.
Hard to say. On a normal day, the primers looked good and no pressure signs. Velocity tracked quickload, for just under max pressure. Hot days I’d pickup 150fps along with the obvious pressure signs. I’ve had similar pressure spikes with 800x in my 10mm.
 

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Quacka: I did a ladder test one day with a .257 and RL-22 powder which is known to be heat sensitive. The day was warming up during the test. Was trying 22 for the first time. Forget where I started and where I finished (lost data in house fire) but was bumping 1/2 grain at a time. Was getting small gains then velocity leveled off at just over 3200 fps. One more bump up and velocity suddenly jumped 200 fps. Primer looked normal. Fired one more just to see if chrono gave a bad number, it didn't. Primer looked okay with that round also. Shoulda stopped just before velocity leveled off but ya don't know till ya try. Pulled all remaining bullets.

I read somewhere, primers don't blow till over 70,000 psi. A lot depends on the rifles chamber and loading method. Oversize chambers and full length sizing can make primers show pressure signs when everything is fine. So can loose primer pockets and other stuff. Pressure is tricky to read when we don't have access to the right tools for the job. Your Quickload is probably trustworthy.
 

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You aren’t truly a handloader until you’re whacking a bolt open with a 2x4 and standing there processing W T F just happened. I like to think it’s wisdom overtaking me as I progress towards geezerhood, and I guess that’s remotely possible, but more likely it’s just a rebalancing of the risk/reward equation. I just don’t chase top speeds anymore. Why?!

Actually, now that I type it out, here’s the main reason. Got my bell rung something fierce about a decade ago. Had to stop shooting recreationally for a few years because it would set off the very distinct symptoms from the brain injury. When I started up again I was much more recoil-averse and prone to a flinch. My point, running my loads well under MAX I think really helps me psychologically when it comes time to cleanly press that trigger. The brass lasts way longer, a big deal with the odd cartridges I seem to prefer, and if the critters notice the missing 100+ fps, none of them have said so. 😗
 

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I read somewhere, primers don't blow till over 70,000 psi. A lot depends on the rifles chamber and loading method. Oversize chambers and full length sizing can make primers show pressure signs when everything is fine. So can loose primer pockets and other stuff. Pressure is tricky to read when we don't have access to the right tools for the job. Your Quickload is probably trustworthy.
Help me understand how full length sizing makes primers show pressure signs when everything is fine?
 

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Pressure isn't hard to figure out. The load manual folks do the heavy lift for you. Many load books list pressure as well as velocity. If you own a chronograph, you can get a pretty good idea of pressure, based on velocity.

If you read about not just your cartridge, but those both bigger and smaller, you should have a fair idea what your window is.

I have a 7x57 in a Ruger #1 (Strong action capable of modern max pressure~65,000psi cartridges). In theory, I should make a little more velocity than the 7mm08 (Which has a few grains less capacity than 7x57). The chronograph told me when I should be good. I could add a little more powder, and make maybe 100fps extra. But on game animals, 100fps isn't going to make any difference. If I get to 280 Remington speeds, I am doing it thru higher pressure. So the chronograph is actually a piece of safety equipment.

If you have a 257 Roberts. And you are getting 25-06 velocity out of it, it's due to higher pressure. Physics say so.
 
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JLG: The way it was explained, it's about headspace and case movement in the chamber when firing. Oil in the chamber or on cases can do the same thing. If the primer isn't supported by the bolt face and the primer pocket is loose, the primer can move as breech pressure rises and when the pressure is sufficient to push the case head back to the bolt face, it can mushroom the primer as it attempts to reseat. I'm betting this situation is extremely rare and so rare it really isn't worth mentioning. When someone says something can happen doesn't mean it actually does. Cases fully fire formed to the chamber dimensions don't move.

Flatfish: A lot of data for older cartridges is geared to older military rifles (Mauser) being converted. We need to look at actual pressure measurements to decide what's applicable to our own rifle. As you said, 65,000 psi is our actual upper limit. New PSI data that supersedes CUP and older data gives most cartridges new maximums. I doubt there's any modern bolt action or Ruger No. 1 that can't handle new pressure maximums. The term "modern" goes back a long way and doesn't mean newly manufactured. About the .25's. When I started loading the .250-3000 for a modern bolt action it became apparent the beginning combustion chamber size meant a great deal. The size is determined by the space within the cartridge case of a loaded round. As the bullet moves down the barrel, the combustion chamber includes the bore. The quicker the bullet accelerates, the quicker the combustion chamber enlarges. All this means something when it comes to pressure. Many large capacity cartridges fall into the "overbore" category, the .25-'06 being one. Large powder charges producing little return. The .257 Roberts is no exception, it just isn't as bad. The .250-3000 is probably ideal for 25 cal. 42 grains of Hybrid 100V produces the same velocity as (book) 48 gr in the Roberts. A tiny bit over 3200 fps. The pressure listed for the Roberts is pretty lame in addition to being listed in CUP. If the data were brought up to modern standards, a proper load of Hybrid 100V would probably push the same bullet used to collect data to 3400 fps. I haven't shot any Hybrid 100V in the Roberts yet so need to rely on published numbers. 52.5 gr in the .25-'06 delivers (book) 3295 fps. Highest velocity listed for the .25-'06 is 3372 FPS with another powder. At the pressure listed, there's still some wiggle room. One thing folks have to know is my data for the .250 and .257 is with rifles set up to have the bullets seated where they belong, not by the book. The beginning combustion chamber is larger because the bullets are seated out farther. For the .257, a full 1/4 inch farther. The .250 might be even farther, I'd have to go measure for an exact number.

I think before anyone starts chasing velocity, they need to find out if their barrel is fast or slow. The only practical way is to compare published data to their own rifle by shooting loads assembled the same as published data. This includes bullet seating depth even if you intend to shoot bullets seated differently. Compare apples to apples. Don't forget barrel length.
 

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JLG: The way it was explained, it's about headspace and case movement in the chamber when firing. Oil in the chamber or on cases can do the same thing. If the primer isn't supported by the bolt face and the primer pocket is loose, the primer can move as breech pressure rises and when the pressure is sufficient to push the case head back to the bolt face, it can mushroom the primer as it attempts to reseat. I'm betting this situation is extremely rare and so rare it really isn't worth mentioning. When someone says something can happen doesn't mean it actually does. Cases fully fire formed to the chamber dimensions don't move.
I see what you're saying, that it is really about excessive headspace. This could be caused by anything that results in too much shoulder setback and not just when one does full length sizing.
 

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JLG: I don't know how much headspace is considered a problem. It's usually referred to as when the primer doesn't receive enough contact with the firing pin for consistent ignition, case head separation, excessive case stretch, poor case life and less than optimum accuracy. There's probably fewer than a handful of rifles these days with too much. I have only one that requires full length sizing for proper case to chamber fit. "Proper" is when chambering a cartridge, there is a slight amount of resistance. Brass doesn't automatically fit the chamber with one firing, might take two or three. I found this out when loading once fired cases that chambered okay. After two firings, I found cases wouldn't fit because case stretching wasn't complete with one. Had to pull some bullets and adjust the sizer all the way to the shell holder, .001" at a time till cases fit chamber. Seems odd a case would stretch beyond the size of the chamber but that's how it worked. Someone probably has an explanation.

When shooting new brass/new rifle, I set the sizer .004"/.005" off the shell holder for initial loading because there's no way to know the exact chamber dimensions. I let fired brass dictate where the sizer should be set.
 

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JLG: I don't know how much headspace is considered a problem. It's usually referred to as when the primer doesn't receive enough contact with the firing pin for consistent ignition, case head separation, excessive case stretch, poor case life and less than optimum accuracy. There's probably fewer than a handful of rifles these days with too much. I have only one that requires full length sizing for proper case to chamber fit. "Proper" is when chambering a cartridge, there is a slight amount of resistance. Brass doesn't automatically fit the chamber with one firing, might take two or three. I found this out when loading once fired cases that chambered okay. After two firings, I found cases wouldn't fit because case stretching wasn't complete with one. Had to pull some bullets and adjust the sizer all the way to the shell holder, .001" at a time till cases fit chamber. Seems odd a case would stretch beyond the size of the chamber but that's how it worked. Someone probably has an explanation.

When shooting new brass/new rifle, I set the sizer .004"/.005" off the shell holder for initial loading because there's no way to know the exact chamber dimensions. I let fired brass dictate where the sizer should be set.
I guess where my mind went is that I get better results with correctly set fl sizing and an expander mandrel than I do with neck sizing. I was concerned some would think fl sizing is inferior and prone to problems.

But lots of bad things happen with too much shoulder setback and thus excessive headspace. Case head separation and bad ignition consistency is just the beginning, as you correctly point out.
 

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I’ve been having fun “off the books”’recently. VV N568 in a 6.5 SAUM, and now Magnum in a 6.5 SAUM. There is 6.5 PRC data out there, which gives a general sense, and if you read enough threads you can usually find SOMEONE else who’s done it, so not flying blind per se, just blind-ish. To your point, I bought a new chrono before embarking on this journey because it’s a crucial data-gathering tool.

In a way, this powder shortage SNAFU has made me up my game, try some new stuff. If I could just buy a pound of H1000 off the shelf at BiMart I certainly wouldn’t be sitting on a small mountain of N568 and Magnum. 😂
 

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Natchez has 7mm ELDM 162’s! 💥 👍 💥
 

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Discussion Starter · #136 ·
I think they are legit. After doing a little research But I’m not positive. Either way their pricing on products and shipping is outrages. I saw they have 210m’s too but not worth gambling at 180 bucks after shipping.
Online reviews of that site are bad! Or did I miss something? I'd buy 2 bricks to have on hand just in case
 

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At this point....I just need primers or I gonna walk around making pew pew noises :)
The nice thing is the pew pew rifle season never closes and there’s no tag required. Hard way to fill the freezer though.

I’m not to that I point yet, but I’m still on the hunt for 215sGM and RL26. I do have 24# of H1000 and don’t currently shoot the stuff, but figured I could trade if I get low. All my buddies shoot it, so I buy it when I can.
 
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