Retumbo in 257 Wby Mag.

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pacobillie

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There are no published loads for Retumbo in 257 Wby Mag for the heavier weight bullets (110-120 gr.) I cannot help but think that it would be the perfect powder for that application. Has anyone tried it?
 
Yes, It works well in my Vanguard 257 Weatherby as well [110-120 grain bullets]
Another newcomer that is working well for me is IMR 8133 [Enduron] Dave.
 
hopefully this Quickload data helps

Code: 
Cartridge          : .[B]257 Weath. Mag[/B]
Bullet             : .257, [B]120, Nosler PART[/B] SP 35643
Useable Case Capaci: 76.728 grain H2O = 4.982 cm³
Cartridge O.A.L. L6: 3.170 inch = 80.52 mm
[B]Barrel Length      : 26.0 inch[/B] = 660.4 mm
Powder             : Hodgdon [B]Retumbo[/B] 

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   91    64.80   3141    2630   45401  13992    100.0    1.369
-09.0   92    65.52   3175    2686   46916  14075    100.0    1.351
-08.0   93    66.24   3209    2743   48491  14156    100.0    1.334
-07.0   94    66.96   3242    2800   50123  14236    100.0    1.317
-06.0   95    67.68   3275    2858   51811  14315    100.0    1.298
-05.0   96    68.40   3308    2916   53566  14393    100.0    1.277
-04.0   97    69.12   3341    2974   55388  14470    100.0    1.258  ! Near Maximum !
-03.0   98    69.84   3374    3032   57276  14546    100.0    1.238  ! Near Maximum !
-02.0   99    70.56   3406    3091   59235  14620    100.0    1.219  ! Near Maximum !
-01.0  100    71.28   3439    3150   61270  14694    100.0    1.200  ! Near Maximum !
+00.0  101    72.00   3471    3210   63377  14766    100.0    1.182  !DANGEROUS LOAD-DO NOT USE!
+01.0  102    72.72   3503    3270   65552  14837    100.0    1.164  !DANGEROUS LOAD-DO NOT USE!
+02.0  103    73.44   3535    3330   67797  14907    100.0    1.146  !DANGEROUS LOAD-DO NOT USE!
+03.0  104    74.16   3567    3391   70117  14976    100.0    1.129  !DANGEROUS LOAD-DO NOT USE!
+04.0  105    74.88   3599    3452   72518  15043    100.0    1.112  !DANGEROUS LOAD-DO NOT USE!
+05.0  106    75.60   3631    3513   75006  15109    100.0    1.095  !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    72.00   3597    3448   77748  14280    100.0    1.089  !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba    101    72.00   3276    2860   50084  15428     99.8    1.304
 
todbartell said:
hopefully this Quickload data helps

Code: 
Cartridge          : .[B]257 Weath. Mag[/B]
Bullet             : .257, [B]120, Nosler PART[/B] SP 35643
Useable Case Capaci: 76.728 grain H2O = 4.982 cm³
Cartridge O.A.L. L6: 3.170 inch = 80.52 mm
[B]Barrel Length      : 26.0 inch[/B] = 660.4 mm
Powder             : Hodgdon [B]Retumbo[/B] 

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   91    64.80   3141    2630   45401  13992    100.0    1.369
-09.0   92    65.52   3175    2686   46916  14075    100.0    1.351
-08.0   93    66.24   3209    2743   48491  14156    100.0    1.334
-07.0   94    66.96   3242    2800   50123  14236    100.0    1.317
-06.0   95    67.68   3275    2858   51811  14315    100.0    1.298
-05.0   96    68.40   3308    2916   53566  14393    100.0    1.277
-04.0   97    69.12   3341    2974   55388  14470    100.0    1.258  ! Near Maximum !
-03.0   98    69.84   3374    3032   57276  14546    100.0    1.238  ! Near Maximum !
-02.0   99    70.56   3406    3091   59235  14620    100.0    1.219  ! Near Maximum !
-01.0  100    71.28   3439    3150   61270  14694    100.0    1.200  ! Near Maximum !
+00.0  101    72.00   3471    3210   63377  14766    100.0    1.182  !DANGEROUS LOAD-DO NOT USE!
+01.0  102    72.72   3503    3270   65552  14837    100.0    1.164  !DANGEROUS LOAD-DO NOT USE!
+02.0  103    73.44   3535    3330   67797  14907    100.0    1.146  !DANGEROUS LOAD-DO NOT USE!
+03.0  104    74.16   3567    3391   70117  14976    100.0    1.129  !DANGEROUS LOAD-DO NOT USE!
+04.0  105    74.88   3599    3452   72518  15043    100.0    1.112  !DANGEROUS LOAD-DO NOT USE!
+05.0  106    75.60   3631    3513   75006  15109    100.0    1.095  !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    72.00   3597    3448   77748  14280    100.0    1.089  !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba    101    72.00   3276    2860   50084  15428     99.8    1.304
Click to expand...

Thanks! Can you run it for a 110 gr. Accubond, which is what I load.
 
Haven't tried it in the 257 Wby, but I have in the larger 257 STW.

Retumbo will be very good in the 257 Wby, but an optimal powder for MV for 100-120 gr bullets would be slightly slower than Re25, H1000, and Retumbo, and be at least as dense as those three powders. Like Eagleye I'd suggest trying IMR-8133, but also Re33.

Of course the powder that produces the highest MV, might not produce the best accuracy.
 
Andy said:
Haven't tried it in the 257 Wby, but I have in the larger 257 STW.

Retumbo will be very good in the 257 Wby, but an optimal powder for MV for 100-120 gr bullets would be slightly slower than Re25, H1000, and Retumbo, and be at least as dense as those three powders. Like Eagleye I'd suggest trying IMR-8133, but also Re33.

Of course the powder that produces the highest MV, might not produce the best accuracy.
Click to expand...

To date, I have used IMR7828 and H1000, with the latter one being ever so slightly more accurate. I was loading 110gr. ELD-X, but after abullet almost blew apart a deer last fall, I have switched to the 110 gr. Accubond. I will restart load development and I am out of H1000. My problem is that H1000 is unobtainium right now, and I amlooking for alternatives.
 
I have used Retumbo in my 257 Wea. Worked up to 75 grs using the Sierra 117 gr SBT with a Fed 215 in a Wea case. Velocity in my Vanguard was 3357 ft/sec with just a tad over 1/2 MOA in 3 shot groups.
 
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