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Load data for .257 Weath. Mag. + .257 | 90gr | Sierra HPBT GameKing

Recommended Powder(s): Alliant Reloder-23, Alliant Reloder-26, Norma MRP, Vihtavuori N555, Winchester StaBALL HD

.257 Weath. Mag. + .257 | 90gr | Sierra HPBT GameKing

Load Specifications

(Use the Personalized Load Calculator below to adjust )

Bullet:
.257 | 90gr | Sierra HPBT GameKing
Manufacturer SKU:
1615
Bullet Weight:
90gr | 5.8g
Bullet Diameter:
0.257" | 6.53mm
Bullet Length:
0.890" | 22.6mm
Caliber:
.257 Weath. Mag. load data
Case Length (l3):
2.549" | 64.7mm
Cartridge Length (C.O.L.):
3.122" | 79.3mm
Seated Depth:
0.317" | 8.0mm
Shank Seated Depth:
0.177" | 4.5mm
Case Capacity:
84.0 Grains of Water | 5.45 cm³
Primer Size:
Large Rifle Magnum (LRM)
Max. allowed Pressure:
63817 psi | 4400 bar
LID:
LID_B5791_C247
Last updated:
2025-02-02
Recommended Twist Rate:
1:13 - 1:11

Load data for 126 loads in caliber .257 Weath. Mag. with .257 | 90gr | Sierra HPBT GameKing bullet and 63 powders such as Alliant Reloder-23, Alliant Reloder-26, Norma MRP, Vihtavuori N555, Winchester StaBALL HD. The key underlying parameters are shown in the table above.

  • Important Notice: DO NOT go below Minimum Charge or above Maximum Charge unless there are reasons. Since xxlreloading.com has no control over the equipment and components used by the customer and the data used in connection with the website, any responsibility and liability for the results achieved is rejected. Also see our Terms of Service

    Questions regarding the load data: Please read the information in the next tab "Explanations".

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    Use the Personalized Load Calculator to customize loads to your own specific requirements. Find more details in the help section.

    Our default view only displays powders/loads that fulfill certain criteria: Max pressure of a load <=90% of Max. Standardized Pressure. Fill Rate (Min FR): >80% and <100% for rife loads,  >60% and <100% for pistol loads. Min. Propellant Combustion (Min z): >90% for rifle loads , >80% for pistol/revolver loads. Relax these criteria at your own risk to potentially get more powders shown in the load tables.

Click on the desired row in the tables below to add a specific load / powder to your Diary and manage there.

Powder
Charge
FR
MaxP
%
V(0)
z
ADI AR 2209
<<locked>>
92%
57377
90%
**88
98%
ADI AR 2213
<<locked>>
95%
57363
90%
**14
97%
[ADI AR 2217]*
<<locked>>
97%
43758
69%
**05
93%
ADI AR 2225
<<locked>>
97%
39276
62%
**40
95%
Accurate 3100
<<locked>>
95%
56971
89%
**19
100%
Accurate 4350
<<locked>>
87%
57276
90%
**45
100%
Accurate MAGPRO
<<locked>>
95%
57014
89%
**10
95%
Alliant Reloder-16
<<locked>>
88%
57116
90%
**01
100%
Alliant Reloder-17
<<locked>>
83%
56565
89%
**94
100%
Alliant Reloder-19
<<locked>>
92%
56637
89%
**65
98%
Alliant Reloder-22
<<locked>>
95%
57217
90%
**17
98%
Alliant Reloder-23 👍
<<locked>>
97%
57014
89%
**78
100%
Alliant Reloder-25
<<locked>>
97%
49676
78%
**92
99%
Alliant Reloder-26 👍
<<locked>>
92%
56768
89%
**43
100%
[Hodgdon H1000]*
<<locked>>
97%
43758
69%
**05
93%
Hodgdon H414
<<locked>>
83%
57348
90%
**88
99%
Hodgdon H4350
<<locked>>
90%
57334
90%
**32
99%
Hodgdon H4831
<<locked>>
97%
55463
87%
**09
96%
Hodgdon H4831 SC
<<locked>>
94%
56695
89%
**32
96%
Hodgdon Hybrid 100V
<<locked>>
90%
56898
89%
**12
100%
Hodgdon LVR
<<locked>>
86%
57203
90%
**65
100%
Hodgdon Retumbo
<<locked>>
97%
39276
62%
**40
95%
Hodgdon Superperformance
<<locked>>
85%
56579
89%
**84
99%
Hodgdon TrailBoss
<<locked>>
96%
34896
55%
**11
100%
IMR 4166 Enduron
<<locked>>
84%
57392
90%
**06
99%
IMR 4350
<<locked>>
89%
57290
90%
**32
99%
IMR 4451 Enduron
<<locked>>
85%
57305
90%
**28
99%
IMR 4831
<<locked>>
92%
56971
89%
**28
100%
IMR 4955 Enduron
<<locked>>
95%
56550
89%
**02
96%
IMR 7828 SSC
<<locked>>
94%
57116
90%
**30
97%
Lovex S065
<<locked>>
86%
57348
90%
**12
100%
Lovex S070
<<locked>>
87%
57217
90%
**19
99%
Lovex S071
<<locked>>
97%
50430
79%
**94
99%
Norma 204
<<locked>>
88%
56840
89%
**61
98%
Norma MRP 👍
<<locked>>
93%
57276
90%
**37
99%
Norma URP
<<locked>>
87%
56521
89%
**55
100%
Ramshot Hunter
<<locked>>
88%
57188
90%
**71
100%
Ramshot Magnum
<<locked>>
95%
56739
89%
**74
99%
ReloadSwiss RS 14
<<locked>>
96%
35607
56%
**60
100%
ReloadSwiss RS 60
<<locked>>
85%
57145
90%
**24
100%
ReloadSwiss RS 62
<<locked>>
86%
56869
89%
**58
100%
ReloadSwiss RS 70
<<locked>>
88%
57392
90%
**27
100%
ReloadSwiss RS 76
<<locked>>
97%
48863
77%
**22
98%
Rottweil R 904
<<locked>>
92%
56971
89%
**32
97%
Rottweil R 905
<<locked>>
93%
57203
90%
**71
98%
Rottweil R 907
<<locked>>
85%
56840
89%
**09
99%
SNPE Vectan Tubal 7000
<<locked>>
86%
56956
89%
**60
99%
Shooters World Long Rifle
<<locked>>
86%
57348
90%
**12
100%
Somchem S355
<<locked>>
83%
57130
90%
**99
100%
Somchem S361
<<locked>>
90%
56681
89%
**69
96%
Somchem S365
<<locked>>
89%
57116
89%
**65
100%
Somchem S385
<<locked>>
93%
57421
90%
**28
99%
Vihtavuori N135
<<locked>>
84%
56971
89%
**14
100%
Vihtavuori N150
<<locked>>
88%
56739
89%
**46
100%
Vihtavuori N160
<<locked>>
85%
56681
89%
**15
100%
Vihtavuori N165
<<locked>>
97%
55129
86%
**69
98%
Vihtavuori N550
<<locked>>
85%
57101
89%
**65
100%
Vihtavuori N555 👍
<<locked>>
94%
57290
90%
**74
100%
Vihtavuori N560
<<locked>>
95%
57116
90%
**20
97%
Vihtavuori N565
<<locked>>
97%
52011
82%
**99
96%
Winchester 6.5 StaBALL
<<locked>>
87%
57130
90%
**76
100%
Winchester 760
<<locked>>
83%
57348
90%
**88
99%
Winchester StaBALL HD 👍
<<locked>>
97%
54563
85%
**53
100%

Max Load - Barrel Length: 23.60''

Powder
Charge
FR
MaxP
%
V(0)
z
[ADI AR 2209]*
<<locked>>
81%
38914
61%
**81
93%
[ADI AR 2213]*
<<locked>>
84%
38363
60%
**77
90%
[ADI AR 2217]*
<<locked>>
92%
37971
60%
**45
90%
[ADI AR 2225]*
<<locked>>
91%
31937
50%
**94
90%
[Accurate 3100]*
<<locked>>
81%
34737
54%
**20
94%
Accurate 4350
<<locked>>
81%
46702
73%
**55
99%
[Accurate MAGPRO]*
<<locked>>
87%
42337
66%
**92
90%
Alliant Reloder-16
<<locked>>
81%
44628
70%
**58
99%
Alliant Reloder-17
<<locked>>
81%
51895
81%
**12
100%
[Alliant Reloder-19]*
<<locked>>
81%
38914
61%
**64
93%
[Alliant Reloder-22]*
<<locked>>
81%
34679
54%
**89
91%
Alliant Reloder-23
<<locked>>
81%
33156
52%
**49
98%
[Alliant Reloder-25]*
<<locked>>
81%
29066
46%
**12
91%
Alliant Reloder-26
<<locked>>
81%
36579
57%
**94
96%
[Hodgdon H1000]*
<<locked>>
92%
37971
60%
**45
90%
Hodgdon H414
<<locked>>
81%
52707
83%
**99
99%
Hodgdon H4350
<<locked>>
81%
42380
66%
**17
95%
[Hodgdon H4831]*
<<locked>>
86%
38798
61%
**45
90%
[Hodgdon H4831 SC]*
<<locked>>
83%
39117
61%
**51
90%
Hodgdon Hybrid 100V
<<locked>>
81%
41930
66%
**20
100%
Hodgdon LVR
<<locked>>
81%
49066
77%
**14
99%
[Hodgdon Retumbo]*
<<locked>>
91%
31937
50%
**94
90%
Hodgdon Superperformance
<<locked>>
81%
48341
76%
**27
97%
Hodgdon TrailBoss
<<locked>>
81%
28036
44%
**37
100%
IMR 4166 Enduron
<<locked>>
81%
52214
82%
**07
98%
IMR 4350
<<locked>>
81%
44846
70%
**69
96%
IMR 4451 Enduron
<<locked>>
81%
50807
80%
**01
98%
IMR 4831
<<locked>>
81%
39987
63%
**81
98%
[IMR 4955 Enduron]*
<<locked>>
82%
38218
60%
**02
90%
[IMR 7828 SSC]*
<<locked>>
83%
38058
60%
**81
90%
Lovex S065
<<locked>>
81%
48153
75%
**32
99%
Lovex S070
<<locked>>
81%
46702
73%
**19
98%
[Lovex S071]*
<<locked>>
81%
29718
47%
**72
92%
Norma 204
<<locked>>
81%
44672
70%
**05
95%
[Norma MRP]*
<<locked>>
81%
36405
57%
**58
93%
Norma URP
<<locked>>
81%
45818
72%
**41
99%
Ramshot Hunter
<<locked>>
81%
44541
70%
**12
98%
[Ramshot Magnum]*
<<locked>>
81%
32489
51%
**00
90%
ReloadSwiss RS 14
<<locked>>
81%
28761
45%
**90
100%
ReloadSwiss RS 60
<<locked>>
81%
49980
78%
**99
100%
ReloadSwiss RS 62
<<locked>>
81%
46673
73%
**61
99%
ReloadSwiss RS 70
<<locked>>
81%
44933
70%
**74
99%
[ReloadSwiss RS 76]*
<<locked>>
86%
32750
51%
**66
90%
[Rottweil R 904]*
<<locked>>
81%
40176
63%
**58
92%
[Rottweil R 905]*
<<locked>>
81%
38130
60%
**45
92%
Rottweil R 907
<<locked>>
81%
49516
78%
**68
98%
SNPE Vectan Tubal 7000
<<locked>>
81%
47674
75%
**73
98%
Shooters World Long Rifle
<<locked>>
81%
48153
75%
**32
99%
Somchem S355
<<locked>>
81%
53388
84%
**37
100%
[Somchem S361]*
<<locked>>
81%
41162
64%
**48
91%
Somchem S365
<<locked>>
81%
42598
67%
**86
100%
[Somchem S385]*
<<locked>>
81%
38841
61%
**35
94%
Vihtavuori N135
<<locked>>
81%
51561
81%
**28
100%
Vihtavuori N150
<<locked>>
81%
46064
72%
**59
100%
Vihtavuori N160
<<locked>>
81%
49327
77%
**71
100%
[Vihtavuori N165]*
<<locked>>
81%
32590
51%
**58
91%
Vihtavuori N550
<<locked>>
81%
49748
78%
**14
99%
Vihtavuori N555
<<locked>>
81%
37231
58%
**51
98%
[Vihtavuori N560]*
<<locked>>
84%
38783
61%
**14
90%
[Vihtavuori N565]*
<<locked>>
88%
38377
60%
**68
90%
Winchester 6.5 StaBALL
<<locked>>
81%
46557
73%
**86
100%
Winchester 760
<<locked>>
81%
52707
83%
**99
99%
Winchester StaBALL HD
<<locked>>
81%
28413
45%
**30
97%

Start Load - Barrel Length: 23.60''

Any powder missing? Then click here.

FR ... fill rate of the cartridge in percent

MaxP ... max. pressure of load in psi or bar

% ... max. pressure of load in percent of the maximum allowed pressure for this caliber 

V(0) ... muzzle velocity in feet per second (fps) or  meters per second (m/s)

z ... powder burnt in percent

[...] *... not dangerous but load has suboptimal powder burnt with possible characteristics such as extensive muzzle flash or inaccurate loads.

[...] ²... fill rate low - you might want to consider using a filler to ensure proper ignition.

[...] ᴾ... possible press load - work up slowly to this load while watching for signs of excessive pressure.

👍  ... recommended powder/load for this caliber and bullet combination based on its ballistic performance.

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