Max loads and AI cases

KDX

KDX

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Do AI chambered cases show max load signs like normal cases? On another forum a guy provided me some data from an older version of Quickload that stated one of the loads I used was +10.0 100 55.33 3656 2226 55487 DANGEROUS LOAD-DO NOT USE!. I had used 55gr of H4350 and a little longer OAL than factory and this showed no pressure signs. Could it be because it is an older version the data isn't right?
 
KDX said:
Do AI chambered cases show max load signs like normal cases? On another forum a guy provided me some data from an older version of Quickload that stated one of the loads I used was +10.0 100 55.33 3656 2226 55487 DANGEROUS LOAD-DO NOT USE!. I had used 55gr of H4350 and a little longer OAL than factory and this showed no pressure signs. Could it be because it is an older version the data isn't right?
Click to expand...


I can run it in the current version if you want, just post all the input info. I inputed some of the loads that I have used for years in different rifles and some have come up as being high pressure in QL....its more of guide than an absolute bible.
 
Pathfinder said:
I can run it in the current version if you want, just post all the input info. I inputed some of the loads that I have used for years in different rifles and some have come up as being high pressure in QL....its more of guide than an absolute bible.
Click to expand...

Thanks for the kind offer. The load in question was 55g of H4350 with an OAL of 2.894 using Winchester +P brass, Winchester magnum primers and 75gr V-Max. Terrible groups though. I did have a 1 hole group with 45gr of XBR with the same brass/primers/OAL/bullet combo. I went up with that powder in 1gr increments and the groups started to open up but when I got to 48gr of powder it shrunk down again and I would like to explore that one further but don't know if I can go any higher or possibly how much higher with that powder. My fire forming loads work well with H335 and I have Benchmark on hand also if you feel like running some numbers with those. You don't have to do those ones if you don't want to.

edit to add...24" barrel, Savage long action.
 
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i found ai cases due to being almost straight walled do not show pressure signs like the parent case. i'm sure you can load into proof pressure zone without seeing much. i know from cronying the loads i have taken a 280ai into rem7 velocitys without any undo signs. i wouldn't go to far past published velocitys just for safety reasons.
 
QL thinks you're loading pipe bombs. Its up to you.

I would use a faster powder for the 75gr.

Cartridge : .257 Ack Imp (257 Rob)
Bullet : .257, 75, Hornady V-MAX 22520
Useable Case Capaci: 60.400 grain H2O = 3.922 cm³
Cartridge O.A.L. L6: 2.894 inch = 73.51 mm
Barrel Length : 24.0 inch = 609.6 mm
Powder : Hodgdon H4350

Predicted data by increasing and decreasing the given charge,
incremented in steps of 0.267% 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

-02.7 98 53.53 3450 1983 50137 10929 93.4 1.047 !DANGEROUS LOAD-DO NOT USE!
-02.4 99 53.68 3460 1994 50564 10960 93.6 1.043 !DANGEROUS LOAD-DO NOT USE!
-02.1 99 53.82 3470 2005 50995 10992 93.7 1.039 !DANGEROUS LOAD-DO NOT USE!
-01.9 99 53.97 3479 2016 51429 11023 93.8 1.035 !DANGEROUS LOAD-DO NOT USE!
-01.6 99 54.12 3489 2027 51867 11054 94.0 1.031 !DANGEROUS LOAD-DO NOT USE!
-01.3 100 54.26 3498 2038 52309 11085 94.1 1.027 !DANGEROUS LOAD-DO NOT USE!
-01.1 100 54.41 3508 2049 52755 11116 94.2 1.023 !DANGEROUS LOAD-DO NOT USE!
-00.8 100 54.56 3518 2061 53205 11146 94.4 1.019 !DANGEROUS LOAD-DO NOT USE!
-00.5 100 54.71 3527 2072 53658 11176 94.5 1.015 !DANGEROUS LOAD-DO NOT USE!
-00.3 101 54.85 3537 2083 54116 11206 94.6 1.011 !DANGEROUS LOAD-DO NOT USE!
+00.0 101 55.00 3546 2094 54577 11236 94.8 1.008 !DANGEROUS LOAD-DO NOT USE!
+00.3 101 55.15 3556 2106 55043 11265 94.9 1.004 !DANGEROUS LOAD-DO NOT USE!
+00.5 102 55.29 3566 2117 55513 11295 95.0 1.000 !DANGEROUS LOAD-DO NOT USE!
+00.8 102 55.44 3575 2129 55987 11324 95.1 0.996 !DANGEROUS LOAD-DO NOT USE!
+01.1 102 55.59 3585 2140 56465 11352 95.2 0.992 !DANGEROUS LOAD-DO NOT USE!
+01.3 102 55.74 3594 2152 56947 11381 95.4 0.988 !DANGEROUS LOAD-DO NOT USE!
Results caused by ± 10% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 10% relative to nominal value:
+Ba 101 55.00 3730 2317 64374 11431 99.0 0.935 !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba 101 55.00 3316 1832 45005 10563 87.2 1.101 ! Near Maximum !


Also ran as .257 roberts Imp. in case the one above was not exactly your chambering.


Cartridge : .257 Roberts Imp.
Bullet : .257, 75, Hornady V-MAX 22520
Useable Case Capaci: 58.855 grain H2O = 3.821 cm³
Cartridge O.A.L. L6: 2.775 inch = 70.49 mm
Barrel Length : 24.0 inch = 609.6 mm
Powder : Hodgdon H4350
Predicted data by increasing and decreasing the given charge,
incremented in steps of 0.267% 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
-02.7 101 53.53 3502 2042 52793 10880 94.0 1.023 !DANGEROUS LOAD-DO NOT USE!
-02.4 101 53.68 3511 2053 53255 10910 94.1 1.019 !DANGEROUS LOAD-DO NOT USE!
-02.1 101 53.82 3521 2065 53720 10941 94.3 1.015 !DANGEROUS LOAD-DO NOT USE!
-01.9 102 53.97 3531 2076 54190 10971 94.4 1.011 !DANGEROUS LOAD-DO NOT USE!
-01.6 102 54.12 3541 2088 54664 11000 94.5 1.007 !DANGEROUS LOAD-DO NOT USE!
-01.3 102 54.26 3551 2099 55143 11030 94.6 1.003 !DANGEROUS LOAD-DO NOT USE!
-01.1 103 54.41 3560 2111 55626 11059 94.8 0.999 !DANGEROUS LOAD-DO NOT USE!
-00.8 103 54.56 3570 2123 56113 11088 94.9 0.995 !DANGEROUS LOAD-DO NOT USE!
-00.5 103 54.71 3580 2134 56605 11117 95.0 0.991 !DANGEROUS LOAD-DO NOT USE!
-00.3 103 54.85 3590 2146 57101 11145 95.1 0.987 !DANGEROUS LOAD-DO NOT USE!
+00.0 104 55.00 3600 2158 57602 11173 95.3 0.983 !DANGEROUS LOAD-DO NOT USE!
+00.3 104 55.15 3609 2170 58107 11201 95.4 0.979 !DANGEROUS LOAD-DO NOT USE!
+00.5 104 55.29 3619 2181 58617 11229 95.5 0.975 !DANGEROUS LOAD-DO NOT USE!
+00.8 104 55.44 3629 2193 59131 11256 95.6 0.972 !DANGEROUS LOAD-DO NOT USE!
+01.1 105 55.59 3639 2205 59651 11284 95.7 0.968 !DANGEROUS LOAD-DO NOT USE!
+01.3 105 55.74 3649 2217 60175 11310 95.9 0.964 !DANGEROUS LOAD-DO NOT USE!
Results caused by ± 10% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 10% relative to nominal value:
+Ba 104 55.00 3782 2383 68014 11316 99.2 0.913 !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba 104 55.00 3369 1890 47451 10547 87.9 1.074 ! Near Maximum !
 
Thanks for the info. I forgot to say at the beginning that I'm loading for the .257 Roberts AI.
 
Here are some of the XBR numbers

food for thought.

Cartridge : .257 Roberts Imp.
Bullet : .257, 75, Hornady V-MAX 22520
Useable Case Capaci: 60.401 grain H2O = 3.922 cm³
Cartridge O.A.L. L6: 2.894 inch = 73.51 mm
Barrel Length : 24.0 inch = 609.6 mm
Powder : IMR 8208 XBR
Predicted data by increasing and decreasing the given charge,
incremented in steps of 0.313% 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
-03.1 82 45.53 3413 1940 48188 10298 98.9 1.066 ! Near Maximum !
-02.8 82 45.68 3423 1951 48605 10322 99.0 1.062 ! Near Maximum !
-02.5 82 45.82 3432 1962 49025 10347 99.1 1.058 ! Near Maximum !
-02.2 83 45.97 3441 1972 49448 10370 99.1 1.054 ! Near Maximum !
-01.9 83 46.12 3451 1983 49874 10394 99.2 1.049 ! Near Maximum !
-01.6 83 46.26 3460 1994 50303 10417 99.2 1.045 ! Near Maximum !
-01.3 83 46.41 3470 2005 50736 10440 99.3 1.041 ! Near Maximum !
-00.9 84 46.56 3479 2016 51173 10463 99.4 1.037 !DANGEROUS LOAD-DO NOT USE!
-00.6 84 46.71 3488 2026 51612 10485 99.4 1.033 !DANGEROUS LOAD-DO NOT USE!
-00.3 84 46.85 3498 2037 52056 10507 99.5 1.029 !DANGEROUS LOAD-DO NOT USE!
+00.0 84 47.00 3507 2048 52502 10529 99.5 1.025 !DANGEROUS LOAD-DO NOT USE!
+00.3 85 47.15 3516 2059 52952 10550 99.5 1.021 !DANGEROUS LOAD-DO NOT USE!
+00.6 85 47.29 3525 2070 53406 10571 99.6 1.017 !DANGEROUS LOAD-DO NOT USE!
+00.9 85 47.44 3535 2081 53863 10592 99.6 1.013 !DANGEROUS LOAD-DO NOT USE!
+01.3 85 47.59 3544 2092 54324 10612 99.7 1.009 !DANGEROUS LOAD-DO NOT USE!
+01.6 86 47.74 3553 2102 54788 10632 99.7 1.005 !DANGEROUS LOAD-DO NOT USE!
Results caused by ± 10% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 10% relative to nominal value:
+Ba 84 47.00 3638 2204 60802 10251 100.0 0.958 !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba 84 47.00 3325 1841 44205 10389 95.5 1.112 ! Near Maximum !
 
It's easy to get into high pressure without the usual signs in AI'd cases.I prefer to use my chrony and I always tend to err on the safe side.I'm looking for a combination of accuracy and velocity that does not always show up in absolute max loads.I load for the .22-250AI,the .25-06AI and the .280AI.Everything has held together so far! Mur
 
KDX said:
Do AI chambered cases show max load signs like normal cases? On another forum a guy provided me some data from an older version of Quickload that stated one of the loads I used was +10.0 100 55.33 3656 2226 55487 DANGEROUS LOAD-DO NOT USE!. I had used 55gr of H4350 and a little longer OAL than factory and this showed no pressure signs. Could it be because it is an older version the data isn't right?
Click to expand...

The Sierra manual has a suggested load of 4350 at 53.2gr and the velocity is screaming at 3700 fps.
Alan do you own a chrony? FS
 
I do own one but it isn't working for some reason. It used to but now it doesn't.:mad: I might have to look at buying another.
 
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