270 wby QL reques

hoyt-6190 · Saturday at 9:16 AM

would someone be willing to run a quick load on the following:
270 wby
Norma brass
140 Partition
Fed 215m
N560
Coal 3.23” and 3.36”

Thanks

DrMike · Saturday at 9:40 AM

Code:

Cartridge          : .270 Weath. Mag.
Bullet             : .277, 140, Nosler PART SP 35200
Useable Case Capaci: 74.231 grain H2O = 4.820 cm³
Cartridge O.A.L. L6: 3.230 inch = 82.04 mm
Barrel Length      : 24.0 inch = 609.6 mm
Powder             : Vihtavuori N560 *C

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   89    62.28   2890    2597   44979  13340     95.0    1.327
-09.0   90    62.97   2924    2657   46522  13503     95.5    1.306
-08.0   91    63.66   2957    2719   48115  13660     96.0    1.285
-07.0   92    64.36   2991    2781   49755  13812     96.4    1.265
-06.0   93    65.05   3024    2844   51442  13959     96.9    1.246
-05.0   94    65.74   3058    2907   53184  14100     97.3    1.226
-04.0   95    66.43   3091    2971   54985  14236     97.6    1.208  ! Near Maximum !
-03.0   96    67.12   3125    3036   56846  14366     98.0    1.189  ! Near Maximum !
-02.0   97    67.82   3158    3101   58770  14489     98.3    1.171  ! Near Maximum !
-01.0   98    68.51   3192    3167   60759  14607     98.6    1.153  ! Near Maximum !
+00.0   99    69.20   3225    3233   62817  14718     98.9    1.135  ! Near Maximum !
+01.0  100    69.89   3258    3300   64945  14822     99.1    1.118  !DANGEROUS LOAD-DO NOT USE!
+02.0  101    70.58   3291    3367   67147  14920     99.3    1.101  !DANGEROUS LOAD-DO NOT USE!
+03.0  102    71.28   3324    3435   69426  15010     99.5    1.084  !DANGEROUS LOAD-DO NOT USE!
+04.0  103    71.97   3357    3504   71784  15094     99.7    1.068  !DANGEROUS LOAD-DO NOT USE!
+05.0  104    72.66   3390    3572   74225  15170     99.8    1.052  !DANGEROUS LOAD-DO NOT USE!

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     99    69.20   3309    3404   69255  14596     99.9    1.088  !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 5% relative to nominal value:
-Ba     99    69.20   3126    3037   56456  14622     96.6    1.190  ! Near Maximum !

DrMike · Saturday at 9:42 AM

Code:

Cartridge          : .270 Weath. Mag.
Bullet             : .277, 140, Nosler PART SP 35200
Useable Case Capaci: 76.215 grain H2O = 4.949 cm³
Cartridge O.A.L. L6: 3.360 inch = 85.34 mm
Barrel Length      : 24.0 inch = 609.6 mm
Powder             : Vihtavuori N560 *C

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   88    63.36   2898    2611   45211  13645     95.2    1.325
-09.0   89    64.06   2931    2671   46744  13809     95.7    1.304
-08.0   90    64.77   2965    2733   48321  13969     96.2    1.284
-07.0   91    65.47   2998    2795   49945  14123     96.6    1.264
-06.0   92    66.18   3032    2857   51623  14272     97.1    1.245
-05.0   93    66.88   3065    2921   53355  14415     97.4    1.225
-04.0   94    67.58   3099    2985   55145  14553     97.8    1.207  ! Near Maximum !
-03.0   95    68.29   3132    3049   56994  14684     98.1    1.188  ! Near Maximum !
-02.0   96    68.99   3165    3114   58905  14810     98.5    1.170  ! Near Maximum !
-01.0   97    69.70   3198    3180   60880  14928     98.7    1.152  ! Near Maximum !
+00.0   98    70.40   3231    3246   62920  15041     99.0    1.135  ! Near Maximum !
+01.0   99    71.10   3264    3313   65030  15146     99.2    1.118  !DANGEROUS LOAD-DO NOT USE!
+02.0  100    71.81   3297    3380   67211  15244     99.4    1.101  !DANGEROUS LOAD-DO NOT USE!
+03.0  101    72.51   3330    3448   69467  15336     99.6    1.084  !DANGEROUS LOAD-DO NOT USE!
+04.0  102    73.22   3363    3516   71800  15420     99.7    1.068  !DANGEROUS LOAD-DO NOT USE!
+05.0  103    73.92   3396    3584   74214  15497     99.8    1.052  !DANGEROUS LOAD-DO NOT USE!

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     98    70.40   3315    3416   69299  14905     99.9    1.088  !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 5% relative to nominal value:
-Ba     98    70.40   3133    3051   56623  14954     96.8    1.189  ! Near Maximum !

hoyt-6190 · Saturday at 12:51 PM

DrMike said:

Code:

Cartridge          : .270 Weath. Mag.
Bullet             : .277, 140, Nosler PART SP 35200
Useable Case Capaci: 76.215 grain H2O = 4.949 cm³
Cartridge O.A.L. L6: 3.360 inch = 85.34 mm
Barrel Length      : 24.0 inch = 609.6 mm
Powder             : Vihtavuori N560 *C

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   88    63.36   2898    2611   45211  13645     95.2    1.325
-09.0   89    64.06   2931    2671   46744  13809     95.7    1.304
-08.0   90    64.77   2965    2733   48321  13969     96.2    1.284
-07.0   91    65.47   2998    2795   49945  14123     96.6    1.264
-06.0   92    66.18   3032    2857   51623  14272     97.1    1.245
-05.0   93    66.88   3065    2921   53355  14415     97.4    1.225
-04.0   94    67.58   3099    2985   55145  14553     97.8    1.207  ! Near Maximum !
-03.0   95    68.29   3132    3049   56994  14684     98.1    1.188  ! Near Maximum !
-02.0   96    68.99   3165    3114   58905  14810     98.5    1.170  ! Near Maximum !
-01.0   97    69.70   3198    3180   60880  14928     98.7    1.152  ! Near Maximum !
+00.0   98    70.40   3231    3246   62920  15041     99.0    1.135  ! Near Maximum !
+01.0   99    71.10   3264    3313   65030  15146     99.2    1.118  !DANGEROUS LOAD-DO NOT USE!
+02.0  100    71.81   3297    3380   67211  15244     99.4    1.101  !DANGEROUS LOAD-DO NOT USE!
+03.0  101    72.51   3330    3448   69467  15336     99.6    1.084  !DANGEROUS LOAD-DO NOT USE!
+04.0  102    73.22   3363    3516   71800  15420     99.7    1.068  !DANGEROUS LOAD-DO NOT USE!
+05.0  103    73.92   3396    3584   74214  15497     99.8    1.052  !DANGEROUS LOAD-DO NOT USE!

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     98    70.40   3315    3416   69299  14905     99.9    1.088  !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 5% relative to nominal value:
-Ba     98    70.40   3133    3051   56623  14954     96.8    1.189  ! Near Maximum !

To understand correctly 100% case fill would 70.40 grains. This data is pretty close to noslers.

Looking at the viht load data for 135gr they show a max 74.2. Any ideas why there would be that much variation? That is with a135 sierra hpbt that is 0.07” longer and viht shows a oal at 3.268”.

DrMike · Saturday at 1:07 PM

hoyt-6190 said:
To understand correctly 100% case fill would 70.40 grains. This data is pretty close to noslers.

Looking at the viht load data for 135gr they show a max 74.2. Any ideas why there would be that much variation? That is with a135 sierra hpbt that is 0.07” longer and viht shows a oal at 3.268”.

There is a difference in bearing surface which introduces a difference in pressure. It can be assumed that differences in metallurgy (composition) and construction introduces a measure of difference. Without taking time to look at what components were used for the test loads, I must assume that these variations introduce a differential. Also, lot-to-lot variation must be taken into account. This is the reason we work up a load carefully, watching for pressure signs rather than just grabbing a recipe and running with it. The recipe is safe in the firing system tested, and it may be safe in your firing system. But you are responsible for yourself when it comes to controlled explosions deliberately set only inches from your face, for that is what firing a cartridge is. Hope that helps.

JD338 · Saturday at 4:39 PM

This

JD338

270 wby QL reques

hoyt-6190

Beginner

DrMike

Ballistician

DrMike

Ballistician

hoyt-6190

Beginner

DrMike

Ballistician

JD338

Range Officer

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