top of page

Load data for .338-378 Weath. Mag. + .338 | 225gr | Hornady GMX

Recommended Powder(s): ADI AR 2213, Alliant Reloder-25, IMR 7828 SSC, ReloadSwiss RS 76, Vihtavuori N560

.338-378 Weath. Mag. + .338 | 225gr | Hornady GMX

Load Specifications

(Use the Personalized Load Calculator below to adjust )

Bullet:
.338 | 225gr | Hornady GMX
Manufacturer SKU:
33201
Bullet Weight:
225gr | 14.6g
Bullet Diameter:
0.338" | 8.59mm
Bullet Length:
1.555" | 39.5mm
Caliber:
.338-378 Weath. Mag. load data
Case Length (l3):
2.910" | 73.9mm
Cartridge Length (C.O.L.):
3.694" | 93.8mm
Seated Depth:
0.771" | 19.6mm
Shank Seated Depth:
0.631" | 16.0mm
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_B2753_C472
Last updated:
2025-09-18
Recommended Twist Rate:
1:12 - 1:10

Load data for 108 loads in caliber .338-378 Weath. Mag. with .338 | 225gr | Hornady GMX bullet and 54 powders such as ADI AR 2213, Alliant Reloder-25, IMR 7828 SSC, ReloadSwiss RS 76, Vihtavuori N560. 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

  • .

    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>>
89%
57188
90%
**40
100%
ADI AR 2213 👍
<<locked>>
91%
56811
89%
**76
99%
ADI AR 2217
<<locked>>
97%
50256
79%
**61
99%
ADI AR 2225
<<locked>>
97%
45281
71%
**15
100%
Accurate 3100
<<locked>>
92%
57406
90%
**77
100%
Accurate MAGPRO
<<locked>>
92%
56971
89%
**86
98%
Alliant Reloder-16
<<locked>>
84%
57014
89%
**30
100%
Alliant Reloder-19
<<locked>>
89%
57130
90%
**33
100%
Alliant Reloder-22
<<locked>>
91%
57130
90%
**63
100%
Alliant Reloder-23
<<locked>>
93%
57217
90%
**17
100%
Alliant Reloder-25 👍
<<locked>>
97%
57043
89%
**76
100%
Alliant Reloder-26
<<locked>>
88%
57246
90%
**92
100%
Alliant Reloder-33
<<locked>>
97%
47268
74%
**61
95%
Hodgdon H1000
<<locked>>
97%
50256
79%
**61
99%
Hodgdon H4350
<<locked>>
87%
57058
89%
**77
100%
Hodgdon H4831
<<locked>>
94%
56913
89%
**10
99%
Hodgdon H4831 SC
<<locked>>
90%
56913
89%
**10
99%
Hodgdon Hybrid 100V
<<locked>>
86%
57421
90%
**54
100%
Hodgdon Retumbo
<<locked>>
97%
45281
71%
**15
100%
Hodgdon TrailBoss
<<locked>>
97%
35926
56%
**11
100%
IMR 4350
<<locked>>
85%
57406
90%
**77
100%
IMR 4831
<<locked>>
88%
57014
89%
**71
100%
IMR 4955 Enduron
<<locked>>
92%
57276
90%
**97
99%
IMR 7828 SSC 👍
<<locked>>
91%
57261
90%
**92
99%
[IMR 7977 Enduron]*
<<locked>>
96%
57029
89%
**38
93%
IMR 8133 Enduron
<<locked>>
97%
41263
65%
**30
97%
Lovex S070
<<locked>>
84%
57101
89%
**74
100%
Lovex S071
<<locked>>
97%
57406
90%
**77
100%
Norma 204
<<locked>>
85%
57261
90%
**13
100%
Norma 217
<<locked>>
97%
41611
65%
**49
99%
Norma MRP
<<locked>>
90%
57377
90%
**89
100%
Norma URP
<<locked>>
84%
56898
89%
**94
100%
Ramshot Hunter
<<locked>>
85%
56942
89%
**13
100%
Ramshot Magnum
<<locked>>
92%
56971
89%
**46
100%
ReloadSwiss RS 14
<<locked>>
97%
36709
58%
**50
100%
ReloadSwiss RS 70
<<locked>>
84%
57029
89%
**49
100%
ReloadSwiss RS 76 👍
<<locked>>
97%
56797
89%
**58
100%
ReloadSwiss RS 80
<<locked>>
97%
52359
82%
**46
98%
Rottweil R 904
<<locked>>
88%
57217
90%
**90
99%
Rottweil R 905
<<locked>>
89%
57421
90%
**36
100%
SNPE Vectan Tubal 7000
<<locked>>
83%
57319
90%
**25
100%
Somchem S361
<<locked>>
87%
57232
90%
**61
99%
Somchem S365
<<locked>>
86%
57276
90%
**84
100%
Somchem S385
<<locked>>
89%
56942
89%
**94
100%
Vihtavuori N150
<<locked>>
85%
57305
90%
**99
100%
Vihtavuori N165
<<locked>>
94%
57261
90%
**81
100%
[Vihtavuori N170]*
<<locked>>
97%
46963
74%
**26
92%
Vihtavuori N555
<<locked>>
90%
57305
90%
**10
100%
Vihtavuori N560 👍
<<locked>>
91%
57363
90%
**92
99%
Vihtavuori N565
<<locked>>
95%
57087
89%
**72
99%
Vihtavuori N568
<<locked>>
97%
53084
83%
**49
98%
Vihtavuori N570
<<locked>>
97%
50734
80%
**46
95%
Winchester 6.5 StaBALL
<<locked>>
83%
56971
89%
**22
100%
Winchester StaBALL HD
<<locked>>
93%
56347
88%
**99
100%

Max Load - Barrel Length: 23.60''

Powder
Charge
FR
MaxP
%
V(0)
z
ADI AR 2209
<<locked>>
81%
44280
69%
**13
98%
ADI AR 2213
<<locked>>
81%
39566
62%
**41
95%
[ADI AR 2217]*
<<locked>>
81%
29530
46%
**72
90%
[ADI AR 2225]*
<<locked>>
81%
26890
42%
**39
92%
Accurate 3100
<<locked>>
81%
40118
63%
**89
99%
[Accurate MAGPRO]*
<<locked>>
81%
39262
62%
**44
93%
Alliant Reloder-16
<<locked>>
81%
50995
80%
**35
100%
Alliant Reloder-19
<<locked>>
81%
44251
69%
**10
98%
Alliant Reloder-22
<<locked>>
81%
40103
63%
**54
97%
Alliant Reloder-23
<<locked>>
81%
38754
61%
**15
100%
Alliant Reloder-25
<<locked>>
81%
33460
52%
**26
98%
Alliant Reloder-26
<<locked>>
81%
43482
68%
**66
100%
[Alliant Reloder-33]*
<<locked>>
90%
37173
58%
**35
90%
[Hodgdon H1000]*
<<locked>>
81%
29530
46%
**72
90%
Hodgdon H4350
<<locked>>
81%
47688
75%
**20
99%
[Hodgdon H4831]*
<<locked>>
81%
37391
59%
**43
94%
Hodgdon H4831 SC
<<locked>>
81%
41481
65%
**41
96%
Hodgdon Hybrid 100V
<<locked>>
81%
47979
75%
**10
100%
[Hodgdon Retumbo]*
<<locked>>
81%
26890
42%
**39
92%
Hodgdon TrailBoss
<<locked>>
81%
28587
45%
**57
100%
IMR 4350
<<locked>>
81%
50212
79%
**72
100%
IMR 4831
<<locked>>
81%
45658
72%
**90
100%
IMR 4955 Enduron
<<locked>>
81%
41176
65%
**98
96%
IMR 7828 SSC
<<locked>>
81%
40785
64%
**77
96%
[IMR 7977 Enduron]*
<<locked>>
90%
46311
73%
**61
90%
[IMR 8133 Enduron]*
<<locked>>
86%
28805
45%
**02
90%
Lovex S070
<<locked>>
81%
52257
82%
**99
100%
Lovex S071
<<locked>>
81%
34403
54%
**64
98%
Norma 204
<<locked>>
81%
50836
80%
**15
99%
[Norma 217]*
<<locked>>
82%
25179
39%
**97
90%
Norma MRP
<<locked>>
81%
42250
66%
**20
99%
Norma URP
<<locked>>
81%
51866
81%
**18
100%
Ramshot Hunter
<<locked>>
81%
50865
80%
**22
100%
Ramshot Magnum
<<locked>>
81%
37405
59%
**95
97%
ReloadSwiss RS 14
<<locked>>
81%
29327
46%
**99
100%
ReloadSwiss RS 70
<<locked>>
81%
51837
81%
**77
100%
ReloadSwiss RS 76
<<locked>>
81%
31749
50%
**20
96%
[ReloadSwiss RS 80]*
<<locked>>
84%
31807
50%
**97
90%
Rottweil R 904
<<locked>>
81%
45455
71%
**90
97%
Rottweil R 905
<<locked>>
81%
43845
69%
**94
98%
SNPE Vectan Tubal 7000
<<locked>>
81%
52736
83%
**53
100%
Somchem S361
<<locked>>
81%
46412
73%
**87
97%
Somchem S365
<<locked>>
81%
49284
77%
**69
100%
Somchem S385
<<locked>>
81%
44222
69%
**80
99%
Vihtavuori N150
<<locked>>
81%
51430
81%
**13
100%
Vihtavuori N165
<<locked>>
81%
37507
59%
**33
97%
[Vihtavuori N170]*
<<locked>>
93%
41031
64%
**08
90%
Vihtavuori N555
<<locked>>
81%
43236
68%
**90
100%
Vihtavuori N560
<<locked>>
81%
40263
63%
**74
95%
[Vihtavuori N565]*
<<locked>>
81%
34795
55%
**33
93%
[Vihtavuori N568]*
<<locked>>
84%
33112
52%
**23
90%
[Vihtavuori N570]*
<<locked>>
89%
38130
60%
**67
90%
Winchester 6.5 StaBALL
<<locked>>
81%
52591
82%
**59
100%
Winchester StaBALL HD
<<locked>>
81%
35679
56%
**44
100%

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.

bottom of page