top of page

Load data for .338-378 Weath. Mag. + .338 | 250gr | Norma GTX

Recommended Powder(s): Hodgdon H4831, ReloadSwiss RS 76, ReloadSwiss RS 80, Vihtavuori N565, Vihtavuori N568

.338-378 Weath. Mag. + .338 | 250gr | Norma GTX

Load Specifications

(Use the Personalized Load Calculator below to adjust )

Bullet:
.338 | 250gr | Norma GTX
Manufacturer SKU:
10685031
Bullet Weight:
250gr | 16.2g
Bullet Diameter:
0.338" | 8.59mm
Bullet Length:
<<locked>>
Caliber:
.338-378 Weath. Mag. load data
Case Length (l3):
2.910" | 73.9mm
Cartridge Length (C.O.L.):
<<locked>>
Seated Depth:
<<locked>>
Shank Seated Depth:
<<locked>>
Case Capacity:
137.0 Grains of Water | 8.90 cm³
Primer Size:
Large Rifle Magnum (LRM)
Max. allowed Pressure:
63817 psi | 4400 bar
LID:
LID_B10819_C472
Last updated:
2025-09-18
Recommended Twist Rate:
1:12 - 1:10

Load data for 0 loads in caliber .338-378 Weath. Mag. with .338 | 250gr | Norma GTX bullet and 0 powders such as Hodgdon H4831, ReloadSwiss RS 76, ReloadSwiss RS 80, Vihtavuori N565, Vihtavuori N568. 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".

  • No data yet

  • 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.

    .

    Loading_icon.gif

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>>
86%
56840
89%
**02
100%
ADI AR 2213
<<locked>>
89%
57116
90%
**44
100%
ADI AR 2217
<<locked>>
97%
55085
86%
**18
100%
ADI AR 2218
<<locked>>
97%
47819
75%
**82
96%
ADI AR 2225
<<locked>>
97%
50227
79%
**85
100%
Accurate 3100
<<locked>>
89%
56826
89%
**40
100%
Accurate MAGPRO
<<locked>>
89%
57276
90%
**64
99%
Alliant Reloder-19
<<locked>>
87%
57406
90%
**08
100%
Alliant Reloder-22
<<locked>>
89%
56956
89%
**31
100%
Alliant Reloder-23
<<locked>>
90%
57087
89%
**72
100%
Alliant Reloder-25
<<locked>>
94%
57130
90%
**38
100%
Alliant Reloder-26
<<locked>>
86%
57290
90%
**54
100%
Alliant Reloder-33
<<locked>>
97%
52968
83%
**44
97%
Alliant Reloder-50
<<locked>>
97%
45063
71%
**97
95%
Baschieri & Pellagri 109
<<locked>>
91%
57145
90%
**99
98%
Bofors RP15 👍
<<locked>>
91%
57406
90%
**38
100%
Bofors RP30 👍
<<locked>>
96%
57014
89%
**61
100%
Bofors RP5
<<locked>>
89%
56956
89%
**31
100%
Hodgdon H1000
<<locked>>
97%
55085
86%
**18
100%
Hodgdon H4831
<<locked>>
92%
57261
90%
**92
100%
Hodgdon H4831 SC
<<locked>>
88%
57377
90%
**99
100%
Hodgdon Hybrid 100V
<<locked>>
84%
56942
89%
**13
100%
Hodgdon Retumbo 👍
<<locked>>
94%
57072
89%
**43
100%
Hodgdon TrailBoss
<<locked>>
97%
36056
57%
**26
100%
IMR 4831
<<locked>>
86%
57334
90%
**43
100%
IMR 4955 Enduron
<<locked>>
89%
57072
89%
**66
100%
IMR 7828 SSC
<<locked>>
88%
57334
90%
**61
100%
IMR 7977 Enduron
<<locked>>
94%
56985
89%
**30
95%
IMR 8133 Enduron
<<locked>>
97%
46253
72%
**03
99%
[Lovex D100]*
<<locked>>
97%
54607
86%
**36
93%
Lovex S071
<<locked>>
94%
57101
89%
**40
100%
Norma 217
<<locked>>
97%
46644
73%
**20
100%
Norma MRP
<<locked>>
87%
57363
90%
**54
100%
Ramshot Grand
<<locked>>
86%
57276
90%
**64
100%
Ramshot Magnum
<<locked>>
89%
57421
90%
**15
100%
ReloadSwiss RS 14
<<locked>>
96%
36912
58%
**65
100%
ReloadSwiss RS 76 👍
<<locked>>
94%
57290
90%
**23
100%
ReloadSwiss RS 80
<<locked>>
96%
57421
90%
**97
100%
Rottweil R 904
<<locked>>
86%
57087
89%
**72
100%
Rottweil R 905
<<locked>>
87%
57421
90%
**02
100%
[SNPE Vectan SP 13]*
<<locked>>
97%
39639
62%
**16
92%
[Shooters World 50 BMG]*
<<locked>>
97%
54607
86%
**36
93%
Somchem S361
<<locked>>
85%
57232
90%
**40
100%
Somchem S385
<<locked>>
86%
56956
89%
**66
100%
Vihtavuori N165
<<locked>>
90%
57087
89%
**49
100%
Vihtavuori N170
<<locked>>
95%
56971
89%
**82
97%
Vihtavuori N555
<<locked>>
87%
56811
89%
**72
100%
Vihtavuori N560
<<locked>>
87%
57377
90%
**67
100%
Vihtavuori N565 👍
<<locked>>
93%
57072
89%
**38
100%
Vihtavuori N568
<<locked>>
96%
57000
89%
**81
99%
Vihtavuori N570
<<locked>>
97%
55854
88%
**10
98%
Winchester StaBALL HD
<<locked>>
90%
57435
90%
**71
100%
Winchester Supreme 780
<<locked>>
86%
56971
89%
**66
100%

Max Load - Barrel Length: 23.60''

Powder
Charge
FR
MaxP
%
V(0)
z
ADI AR 2209
<<locked>>
81%
48211
76%
**71
100%
ADI AR 2213
<<locked>>
81%
43279
68%
**08
98%
[ADI AR 2217]*
<<locked>>
81%
32242
51%
**52
94%
[ADI AR 2218]*
<<locked>>
89%
35926
56%
**03
90%
ADI AR 2225
<<locked>>
81%
29501
46%
**26
96%
Accurate 3100
<<locked>>
81%
43874
69%
**36
100%
Accurate MAGPRO
<<locked>>
81%
43091
68%
**12
96%
Alliant Reloder-19
<<locked>>
81%
47964
75%
**51
99%
Alliant Reloder-22
<<locked>>
81%
43932
69%
**15
99%
Alliant Reloder-23
<<locked>>
81%
42656
67%
**59
100%
Alliant Reloder-25
<<locked>>
81%
36753
58%
**00
100%
Alliant Reloder-26
<<locked>>
81%
48196
76%
**13
100%
[Alliant Reloder-33]*
<<locked>>
85%
33881
53%
**48
90%
[Alliant Reloder-50]*
<<locked>>
90%
35012
55%
**74
90%
Baschieri & Pellagri 109
<<locked>>
81%
41916
66%
**30
95%
Bofors RP15
<<locked>>
81%
40886
64%
**49
98%
Bofors RP30
<<locked>>
81%
34287
54%
**28
95%
Bofors RP5
<<locked>>
81%
43932
69%
**15
99%
[Hodgdon H1000]*
<<locked>>
81%
32242
51%
**52
94%
Hodgdon H4831
<<locked>>
81%
40582
64%
**07
97%
Hodgdon H4831 SC
<<locked>>
81%
45266
71%
**92
98%
Hodgdon Hybrid 100V
<<locked>>
81%
51880
81%
**38
100%
Hodgdon Retumbo
<<locked>>
81%
36027
56%
**39
98%
Hodgdon TrailBoss
<<locked>>
81%
28747
45%
**78
100%
IMR 4831
<<locked>>
81%
49676
78%
**38
100%
IMR 4955 Enduron
<<locked>>
81%
44498
70%
**49
98%
IMR 7828 SSC
<<locked>>
81%
44614
70%
**48
98%
[IMR 7977 Enduron]*
<<locked>>
84%
41553
65%
**61
90%
[IMR 8133 Enduron]*
<<locked>>
81%
26963
42%
**44
91%
[Lovex D100]*
<<locked>>
92%
45397
71%
**79
90%
Lovex S071
<<locked>>
81%
37927
59%
**21
99%
[Norma 217]*
<<locked>>
81%
26977
42%
**60
94%
Norma MRP
<<locked>>
81%
46746
73%
**87
100%
Ramshot Grand
<<locked>>
81%
47398
74%
**07
99%
Ramshot Magnum
<<locked>>
81%
41510
65%
**66
99%
ReloadSwiss RS 14
<<locked>>
81%
29573
46%
**17
100%
ReloadSwiss RS 76
<<locked>>
81%
35201
55%
**10
99%
[ReloadSwiss RS 80]*
<<locked>>
81%
32053
50%
**98
92%
Rottweil R 904
<<locked>>
81%
48892
77%
**38
99%
Rottweil R 905
<<locked>>
81%
47601
75%
**48
100%
[SNPE Vectan SP 13]*
<<locked>>
94%
35418
55%
**28
90%
[Shooters World 50 BMG]*
<<locked>>
92%
45397
71%
**79
90%
Somchem S361
<<locked>>
81%
49879
78%
**28
99%
Somchem S385
<<locked>>
81%
48196
76%
**31
100%
Vihtavuori N165
<<locked>>
81%
41959
66%
**10
99%
[Vihtavuori N170]*
<<locked>>
82%
36782
58%
**11
90%
Vihtavuori N555
<<locked>>
81%
47442
74%
**28
100%
Vihtavuori N560
<<locked>>
81%
46412
73%
**80
98%
Vihtavuori N565
<<locked>>
81%
38406
60%
**07
96%
[Vihtavuori N568]*
<<locked>>
81%
33417
52%
**21
92%
[Vihtavuori N570]*
<<locked>>
83%
34650
54%
**77
90%
Winchester StaBALL HD
<<locked>>
81%
40582
64%
**08
100%
Winchester Supreme 780
<<locked>>
81%
48225
76%
**28
99%

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

bottom of page