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Just ran out to the hayfield to run ladder test on my 264WM
Did 62-66gr in 1gr steps of IMR7828 behind a 140gr Accubond.
New brass, Winchester LRM primers
62 and 64gr showed 1.5" at 200yds.
3042 and 3142fps on magnetospeed.
Bolt lift was stiff at 65gr.
Popped a primer at 66.
6700ft elevation and 90degrees
Any ballpark guesses at my pressures?
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You say new brass, but you don't mention what brand. You can get a 6k pressure change just by changing headstamp.
QL puts your 66gr load, at 70 degrees at 68K PSI.
If you are popping primers, you are probably north of 75K PSI.
Last edited by antelope_sniper; 08/30/15.
You didn't use logic or reason to get into this opinion, I cannot use logic or reason to get you out of it.
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R-P brass, 3.210" to answer both questions.
Never used Q-L so don't know all the parameters needed. Know the 264 doesn't really "shine" until you get towards upper end but I've never shot it when it was this hot out and the first time I ever popped a primer. I like the looks of the 64gr load but will wait until it's a little cooler out to try it again.
Thanks for your help.
Last edited by tmax264; 08/30/15.
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On average, RP brass is on the thick side and adds pressure. On a hot day, you could of been as high as 80k.
Last edited by antelope_sniper; 08/30/15.
You didn't use logic or reason to get into this opinion, I cannot use logic or reason to get you out of it.
You cannot over estimate the unimportance of nearly everything. John Maxwell
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To be accurate QL needs actual case capacity of a fired case in grains of H20.
Give a man a fish and he eats for a day. Give a man a welfare check, a forty ounce malt liquor, a crack pipe, an Obama phone, free health insurance. and some Air Jordan's and he votes Democrat for a lifetime.
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To be accurate QL needs actual case capacity of a fired case in grains of H20. If you have Quickload you also need a chronograph and change the burn rate in Quickload until the velocities match. And even then there are so many other factors you still only have a computer generated guesstimate. I have Quickload and it gives you a lot of information, but it requires "tweaking" to get good "estimates". So QL and all the reloading manuals are all ball park figures because of variations in rifles and there components.
Last edited by bigedp51; 08/31/15.
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I am working the very same combination in a new-to-me pre-64 Model 70, except I am using some brass headstamped W-W Super. I have fired only the preliminary loads so far, but I found that 63.1 and 63.5 grains of 7828 each gave me 0.99" three-shot groups, and velocities just north of 3100 fps. Here's what QuickLOAD shows. I would point out that I am using the water capacity for my own cases (at least I THINK that's my value, could be the program default...can't recall whether I actually edited the file or not). Cartridge : .264 Win. Mag.
Bullet : .264, 140, Nosler AccuBond 39457
Useable Case Capaci: 78.258 grain H2O = 5.081 cm³
Cartridge O.A.L. L6: 3.340 inch = 84.84 mm
Barrel Length : 26.0 inch = 660.4 mm
Powder : IMR 7828
Predicted data by increasing and decreasing the given charge,
incremented in steps of 1.0% of nominal charge.
CAUTION: Figures exceed maximum and minimum recommended loads !
Step Fill. Charge Vel. Energy Pmax Pmuz Prop.Burnt B_Time
% % Grains fps ft.lbs psi psi % ms
-10.0 83 58.50 2821 2474 42553 12824 98.1 1.506
-09.0 84 59.15 2851 2527 43915 12952 98.4 1.484
-08.0 85 59.80 2881 2580 45313 13075 98.7 1.462
-07.0 86 60.45 2911 2634 46747 13192 98.9 1.441
-06.0 87 61.10 2941 2689 48217 13303 99.2 1.420
-05.0 88 61.75 2971 2743 49730 13409 99.4 1.400
-04.0 89 62.40 3000 2799 51286 13509 99.6 1.380
-03.0 90 63.05 3030 2854 52889 13603 99.7 1.360
-02.0 91 63.70 3059 2910 54539 13691 99.8 1.340 ! Near Maximum !
-01.0 92 64.35 3089 2966 56238 13772 99.9 1.321 ! Near Maximum !
+00.0 93 65.00 3118 3022 57987 13846 100.0 1.303 ! Near Maximum !
+01.0 94 65.65 3147 3078 59788 13915 100.0 1.285 ! Near Maximum !
+02.0 95 66.30 3176 3135 61643 13977 100.0 1.267
+03.0 96 66.95 3204 3192 63553 14037 100.0 1.249
+04.0 96 67.60 3233 3249 65521 14096 100.0 1.232
+05.0 97 68.25 3261 3306 67549 14155 100.0 1.215
Results caused by ± 5% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 5% relative to nominal value:
+Ba 93 65.00 3186 3156 63598 13576 100.0 1.251 !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 5% relative to nominal value:
-Ba 93 65.00 3034 2862 52394 13977 99.0 1.362
Don't be the darkness.
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I would also point out that I have not adjusted burn rate in QL, I generally don't mess with it. What I DO watch is the velocity shown at a reasonable maximum pressure, which in this case would be 3176 fps @ 61643 psi. My approach is that my pressures are presumably reasonable as long as I keep velocities under 3176 fps. In my case, groups started opening up at 63.9 grains of 7828 and velocities suggested I was at 65000 psi anyway.
Next time out I will be trying loads with closer charge intervals and hopefully something better than 0.99" will happen.
Don't be the darkness.
America will perish while those who should be standing guard are satisfying their lusts.
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