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Load data for .256 Mag. Gibbs + .257 | 100gr | Impala RNFP KO

Recommended Powder(s):

.256 Mag. Gibbs + .257 | 100gr | Impala RNFP KO

Load Specifications

(Use the Personalized Load Calculator below to adjust )

Bullet:
.257 | 100gr | Impala RNFP KO
Bullet Weight:
100gr | 6.5g
Bullet Diameter:
0.257" | 6.53mm
Bullet Length:
<<locked>>
Caliber:
.256 Mag. Gibbs load data
Case Length (l3):
2.173" | 55.2mm
Cartridge Length (C.O.L.):
<<locked>>
Seated Depth:
<<locked>>
Shank Seated Depth:
<<locked>>
Case Capacity:
56.0 Grains of Water | 3.64 cm³
Primer Size:
Large Rifle (LR)
Max. allowed Pressure:
49313 psi | 3400 bar
LID:
LID_B2973_C231
Last updated:
2026-03-25

Load data for 94 loads in caliber .256 Mag. Gibbs with .257 | 100gr | Impala RNFP KO bullet and 47 powder(s). 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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  • We recommend you limit powder range to relevant brands to speed up re-calculation of results

    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.

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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
[Accurate 2700]*
<<locked>>
83%
44150
90%
**95
93%
[Accurate 3100]*
<<locked>>
97%
41292
84%
**51
94%
Accurate 4350
<<locked>>
89%
43714
89%
**36
97%
Alliant Reloder-16
<<locked>>
90%
43758
89%
**63
97%
Alliant Reloder-17 👍
<<locked>>
87%
44150
90%
**99
99%
[Alliant Reloder-19]*
<<locked>>
95%
44164
90%
**27
92%
Alliant Reloder-23
<<locked>>
97%
38972
79%
**74
98%
Alliant Reloder-26
<<locked>>
97%
43163
88%
**31
97%
[Bofors RP7]*
<<locked>>
86%
44048
89%
**48
93%
[Hodgdon H414]*
<<locked>>
85%
43656
89%
**30
94%
[Hodgdon H4350]*
<<locked>>
91%
44034
89%
**67
93%
Hodgdon Hybrid 100V 👍
<<locked>>
93%
43888
89%
**20
99%
Hodgdon LVR
<<locked>>
87%
43642
88%
**23
96%
[Hodgdon Superperformance]*
<<locked>>
88%
44237
90%
**59
93%
Hodgdon TrailBoss
<<locked>>
96%
34447
70%
**96
100%
IMR 4064
<<locked>>
83%
44309
90%
**61
98%
[IMR 4350]*
<<locked>>
89%
43598
88%
**54
93%
[IMR 4451 Enduron]*
<<locked>>
85%
44077
89%
**51
94%
IMR 4831
<<locked>>
94%
44295
90%
**27
97%
Lovex S065
<<locked>>
87%
44309
90%
**61
96%
[Lovex S070]*
<<locked>>
88%
44150
90%
**77
94%
[Lovex S071]*
<<locked>>
97%
35012
71%
**97
92%
[Norma MRP]*
<<locked>>
97%
43033
87%
**72
93%
Norma URP
<<locked>>
90%
44295
90%
**46
97%
Ramshot Hunter
<<locked>>
91%
44367
90%
**56
95%
ReloadSwiss RS 14
<<locked>>
96%
34606
70%
**36
100%
ReloadSwiss RS 60
<<locked>>
85%
44179
90%
**05
100%
ReloadSwiss RS 62
<<locked>>
90%
43947
89%
**63
97%
ReloadSwiss RS 70
<<locked>>
90%
43787
89%
**72
96%
Rottweil R 903
<<locked>>
84%
43990
89%
**90
99%
[Rottweil R 905]*
<<locked>>
96%
43787
89%
**23
92%
[Rottweil R 907]*
<<locked>>
86%
44048
89%
**48
93%
SNPE Vectan SP 11
<<locked>>
84%
44222
90%
**27
98%
SNPE Vectan Tubal 5000
<<locked>>
83%
44295
90%
**85
100%
[SNPE Vectan Tubal 7000]*
<<locked>>
87%
43671
89%
**99
94%
Shooters World Long Rifle
<<locked>>
87%
44309
90%
**61
96%
Somchem S355
<<locked>>
84%
44222
90%
**87
99%
Somchem S365 👍
<<locked>>
93%
43990
89%
**89
100%
[Somchem S385]*
<<locked>>
95%
43613
88%
**97
93%
Vihtavuori N135
<<locked>>
85%
44222
90%
**35
100%
Vihtavuori N150
<<locked>>
88%
43743
89%
**44
99%
Vihtavuori N160
<<locked>>
87%
44237
90%
**07
97%
Vihtavuori N550
<<locked>>
87%
43816
89%
**30
97%
Vihtavuori N555
<<locked>>
96%
42409
86%
**56
98%
Winchester 6.5 StaBALL
<<locked>>
89%
43990
89%
**74
99%
[Winchester 760]*
<<locked>>
85%
43656
89%
**30
94%
Winchester StaBALL HD
<<locked>>
97%
35099
71%
**54
97%

Max Load - Barrel Length: 23.60''

Powder
Charge
FR
MaxP
%
V(0)
z
[Accurate 2700]*
<<locked>>
81%
40915
83%
**23
92%
[Accurate 3100]*
<<locked>>
89%
31778
64%
**12
90%
[Accurate 4350]*
<<locked>>
81%
33417
68%
**87
94%
[Alliant Reloder-16]*
<<locked>>
81%
33402
68%
**87
93%
Alliant Reloder-17
<<locked>>
81%
37057
75%
**22
97%
[Alliant Reloder-19]*
<<locked>>
92%
40190
81%
**38
90%
[Alliant Reloder-23]*
<<locked>>
82%
25889
52%
**64
90%
[Alliant Reloder-26]*
<<locked>>
87%
31473
64%
**00
90%
[Bofors RP7]*
<<locked>>
81%
38653
78%
**20
91%
[Hodgdon H414]*
<<locked>>
81%
38159
77%
**95
92%
[Hodgdon H4350]*
<<locked>>
86%
36956
75%
**03
90%
[Hodgdon Hybrid 100V]*
<<locked>>
81%
30850
63%
**92
94%
[Hodgdon LVR]*
<<locked>>
81%
35984
73%
**40
94%
[Hodgdon Superperformance]*
<<locked>>
83%
37507
76%
**92
90%
Hodgdon TrailBoss
<<locked>>
81%
27644
56%
**42
100%
IMR 4064
<<locked>>
81%
41539
84%
**99
97%
[IMR 4350]*
<<locked>>
83%
36056
73%
**84
90%
[IMR 4451 Enduron]*
<<locked>>
81%
39334
80%
**43
92%
[IMR 4831]*
<<locked>>
81%
29704
60%
**62
92%
[Lovex S065]*
<<locked>>
81%
37492
76%
**07
93%
[Lovex S070]*
<<locked>>
81%
35737
72%
**74
91%
[Lovex S071]*
<<locked>>
94%
31778
64%
**12
90%
[Norma MRP]*
<<locked>>
92%
36999
75%
**22
90%
[Norma URP]*
<<locked>>
81%
33736
68%
**94
93%
[Ramshot Hunter]*
<<locked>>
81%
32793
67%
**57
90%
ReloadSwiss RS 14
<<locked>>
81%
27833
56%
**78
100%
ReloadSwiss RS 60
<<locked>>
81%
39363
80%
**04
100%
[ReloadSwiss RS 62]*
<<locked>>
81%
32880
67%
**87
93%
[ReloadSwiss RS 70]*
<<locked>>
81%
32822
67%
**77
91%
Rottweil R 903
<<locked>>
81%
40640
82%
**18
98%
[Rottweil R 905]*
<<locked>>
92%
39624
80%
**25
90%
[Rottweil R 907]*
<<locked>>
81%
38653
78%
**20
91%
SNPE Vectan SP 11
<<locked>>
81%
40814
83%
**51
97%
SNPE Vectan Tubal 5000
<<locked>>
81%
41829
85%
**43
100%
[SNPE Vectan Tubal 7000]*
<<locked>>
81%
36347
74%
**35
91%
[Shooters World Long Rifle]*
<<locked>>
81%
37492
76%
**07
93%
Somchem S355
<<locked>>
81%
40988
83%
**22
98%
Somchem S365
<<locked>>
81%
30501
62%
**41
96%
[Somchem S385]*
<<locked>>
89%
36695
74%
**33
90%
Vihtavuori N135
<<locked>>
81%
39827
81%
**53
100%
Vihtavuori N150
<<locked>>
81%
35230
71%
**54
98%
Vihtavuori N160
<<locked>>
81%
36260
74%
**23
95%
Vihtavuori N550
<<locked>>
81%
36869
75%
**62
95%
[Vihtavuori N555]*
<<locked>>
81%
26556
54%
**16
90%
Winchester 6.5 StaBALL
<<locked>>
81%
34664
70%
**64
96%
[Winchester 760]*
<<locked>>
81%
38159
77%
**95
92%
[Winchester StaBALL HD]*
<<locked>>
88%
27325
55%
**66
90%

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.

<<locked>>... you need to buy an access license to unlock the data

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