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Load data for .378 Weath. Mag. + .375 | 300gr | Speer AGS TBSS

Recommended Powder(s): ADI AR 2209, Alliant Reloder-19, Alliant Reloder-22, Norma MRP, Ramshot Magnum

.378 Weath. Mag. + .375 | 300gr | Speer AGS TBSS

Load Specifications

(Use the Personalized Load Calculator below to adjust )

Bullet:
.375 | 300gr | Speer AGS TBSS
Manufacturer SKU:
1781
Bullet Weight:
300gr | 19.4g
Bullet Diameter:
0.375" | 9.52mm
Bullet Length:
1.200" | 30.5mm
Caliber:
.378 Weath. Mag. load data
Case Length (l3):
2.913" | 74.0mm
Cartridge Length (C.O.L.):
3.600" | 91.4mm
Seated Depth:
0.513" | 13.0mm
Shank Seated Depth:
0.513" | 13.0mm
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_B6248_C577
Last updated:
2025-01-01

Load data for 130 loads in caliber .378 Weath. Mag. with .375 | 300gr | Speer AGS TBSS bullet and 65 powders such as ADI AR 2209, Alliant Reloder-19, Alliant Reloder-22, Norma MRP, Ramshot Magnum. 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%
57188
90%
**82
100%
ADI AR 2213
<<locked>>
95%
56927
89%
**15
99%
ADI AR 2217
<<locked>>
97%
44208
69%
**89
97%
ADI AR 2225
<<locked>>
97%
39305
62%
**52
98%
Accurate 3100
<<locked>>
95%
57203
90%
**23
100%
Accurate 4350
<<locked>>
86%
57377
90%
**40
100%
Accurate MAGPRO
<<locked>>
96%
57087
89%
**31
98%
Alliant Reloder-16
<<locked>>
88%
56985
89%
**69
100%
Alliant Reloder-17
<<locked>>
83%
57261
90%
**76
100%
Alliant Reloder-19 👍
<<locked>>
92%
57377
90%
**79
100%
Alliant Reloder-22 👍
<<locked>>
95%
56884
89%
**08
100%
Alliant Reloder-23
<<locked>>
97%
56913
89%
**62
100%
Alliant Reloder-25
<<locked>>
97%
49893
78%
**33
100%
Alliant Reloder-26
<<locked>>
92%
56840
89%
**51
100%
Hodgdon H1000
<<locked>>
97%
44208
69%
**89
97%
Hodgdon H414
<<locked>>
83%
57319
90%
**62
100%
Hodgdon H4350
<<locked>>
90%
57087
89%
**20
100%
Hodgdon H4831
<<locked>>
97%
55434
87%
**36
98%
Hodgdon H4831 SC
<<locked>>
94%
57058
89%
**53
98%
Hodgdon Hybrid 100V
<<locked>>
90%
57363
90%
**97
100%
Hodgdon LVR
<<locked>>
85%
57392
90%
**36
100%
Hodgdon Retumbo
<<locked>>
97%
39305
62%
**52
98%
Hodgdon Superperformance
<<locked>>
85%
57174
90%
**92
100%
IMR 4166 Enduron
<<locked>>
83%
57116
90%
**71
100%
IMR 4350
<<locked>>
88%
57043
89%
**17
100%
IMR 4451 Enduron
<<locked>>
84%
57261
90%
**00
100%
IMR 4831
<<locked>>
92%
57246
90%
**23
100%
IMR 4955 Enduron
<<locked>>
95%
57101
89%
**30
99%
IMR 7828 SSC
<<locked>>
94%
57058
89%
**28
99%
[IMR 8133 Enduron]*
<<locked>>
97%
35578
56%
**61
94%
Lovex S065
<<locked>>
86%
57334
90%
**87
100%
Lovex S070
<<locked>>
87%
57203
90%
**17
100%
Lovex S071
<<locked>>
97%
50647
79%
**35
100%
Norma 204
<<locked>>
88%
57406
90%
**59
99%
Norma 217
<<locked>>
97%
35404
55%
**84
96%
Norma MRP 👍
<<locked>>
93%
56971
89%
**31
100%
Norma URP
<<locked>>
87%
57116
89%
**40
100%
Ramshot Hunter
<<locked>>
88%
57363
90%
**69
100%
Ramshot Magnum 👍
<<locked>>
96%
56913
89%
**95
100%
ReloadSwiss RS 14
<<locked>>
97%
36521
57%
**96
100%
ReloadSwiss RS 60
<<locked>>
84%
57203
90%
**89
100%
ReloadSwiss RS 62
<<locked>>
86%
57116
89%
**56
100%
ReloadSwiss RS 70
<<locked>>
87%
57203
90%
**05
100%
ReloadSwiss RS 76
<<locked>>
97%
48776
76%
**82
100%
ReloadSwiss RS 80
<<locked>>
97%
43671
68%
**54
95%
Rottweil R 904
<<locked>>
91%
57261
90%
**36
99%
Rottweil R 905
<<locked>>
93%
56884
89%
**72
100%
Rottweil R 907
<<locked>>
85%
57348
90%
**03
100%
SNPE Vectan Tubal 7000
<<locked>>
86%
57217
90%
**57
100%
Shooters World Long Rifle
<<locked>>
86%
57334
90%
**87
100%
Somchem S361
<<locked>>
91%
57377
90%
**10
98%
Somchem S365
<<locked>>
89%
56869
89%
**33
100%
Somchem S385
<<locked>>
92%
57116
90%
**40
100%
Vihtavuori N135
<<locked>>
84%
57406
90%
**89
100%
Vihtavuori N150
<<locked>>
88%
57363
90%
**38
100%
Vihtavuori N160
<<locked>>
85%
57116
89%
**00
100%
Vihtavuori N165
<<locked>>
97%
55753
87%
**03
100%
Vihtavuori N550
<<locked>>
85%
57246
90%
**40
100%
Vihtavuori N555
<<locked>>
94%
57334
90%
**62
100%
Vihtavuori N560
<<locked>>
95%
56956
89%
**41
99%
Vihtavuori N565
<<locked>>
97%
52011
81%
**46
98%
Vihtavuori N568
<<locked>>
97%
45440
71%
**71
95%
Winchester 6.5 StaBALL
<<locked>>
87%
56956
89%
**71
100%
Winchester 760
<<locked>>
83%
57319
90%
**62
100%
Winchester StaBALL HD
<<locked>>
97%
54853
86%
**54
100%

Max Load - Barrel Length: 23.60''

Powder
Charge
FR
MaxP
%
V(0)
z
ADI AR 2209
<<locked>>
81%
39856
62%
**77
96%
[ADI AR 2213]*
<<locked>>
81%
35433
56%
**02
93%
[ADI AR 2217]*
<<locked>>
85%
30501
48%
**64
90%
[ADI AR 2225]*
<<locked>>
83%
25744
40%
**62
90%
Accurate 3100
<<locked>>
81%
35781
56%
**59
98%
Accurate 4350
<<locked>>
81%
47688
75%
**95
100%
[Accurate MAGPRO]*
<<locked>>
81%
34185
54%
**92
90%
Alliant Reloder-16
<<locked>>
81%
45469
71%
**98
100%
Alliant Reloder-17
<<locked>>
81%
52678
83%
**10
100%
Alliant Reloder-19
<<locked>>
81%
39726
62%
**64
96%
Alliant Reloder-22
<<locked>>
81%
35418
55%
**11
95%
Alliant Reloder-23
<<locked>>
81%
34200
54%
**79
100%
Alliant Reloder-25
<<locked>>
81%
29834
47%
**00
96%
Alliant Reloder-26
<<locked>>
81%
37217
58%
**13
99%
[Hodgdon H1000]*
<<locked>>
85%
30501
48%
**64
90%
Hodgdon H414
<<locked>>
81%
53461
84%
**10
100%
Hodgdon H4350
<<locked>>
81%
43482
68%
**87
98%
[Hodgdon H4831]*
<<locked>>
81%
33533
53%
**13
91%
[Hodgdon H4831 SC]*
<<locked>>
81%
37130
58%
**02
93%
Hodgdon Hybrid 100V
<<locked>>
81%
42931
67%
**84
100%
Hodgdon LVR
<<locked>>
81%
50009
78%
**28
100%
[Hodgdon Retumbo]*
<<locked>>
83%
25744
40%
**62
90%
Hodgdon Superperformance
<<locked>>
81%
48646
76%
**61
99%
IMR 4166 Enduron
<<locked>>
81%
53417
84%
**25
100%
IMR 4350
<<locked>>
81%
45614
71%
**33
99%
IMR 4451 Enduron
<<locked>>
81%
51764
81%
**15
100%
IMR 4831
<<locked>>
81%
41278
65%
**70
100%
[IMR 4955 Enduron]*
<<locked>>
81%
37434
59%
**72
94%
[IMR 7828 SSC]*
<<locked>>
81%
36318
57%
**38
94%
[IMR 8133 Enduron]*
<<locked>>
91%
29820
47%
**06
90%
Lovex S065
<<locked>>
81%
49197
77%
**69
100%
Lovex S070
<<locked>>
81%
47427
74%
**62
99%
Lovex S071
<<locked>>
81%
30661
48%
**34
96%
Norma 204
<<locked>>
81%
45513
71%
**69
98%
[Norma 217]*
<<locked>>
87%
25759
40%
**01
90%
Norma MRP
<<locked>>
81%
37101
58%
**80
97%
Norma URP
<<locked>>
81%
46615
73%
**75
100%
Ramshot Hunter
<<locked>>
81%
45397
71%
**75
100%
Ramshot Magnum
<<locked>>
81%
32648
51%
**49
95%
ReloadSwiss RS 14
<<locked>>
91%
33881
53%
**47
100%
ReloadSwiss RS 60
<<locked>>
81%
50778
80%
**00
100%
ReloadSwiss RS 62
<<locked>>
81%
47500
74%
**15
100%
ReloadSwiss RS 70
<<locked>>
81%
45411
71%
**25
100%
[ReloadSwiss RS 76]*
<<locked>>
81%
28036
44%
**70
92%
[ReloadSwiss RS 80]*
<<locked>>
89%
32982
52%
**05
90%
Rottweil R 904
<<locked>>
81%
41089
64%
**51
96%
Rottweil R 905
<<locked>>
81%
38899
61%
**54
96%
Rottweil R 907
<<locked>>
81%
50473
79%
**95
99%
SNPE Vectan Tubal 7000
<<locked>>
81%
48327
76%
**23
99%
Shooters World Long Rifle
<<locked>>
81%
49197
77%
**69
100%
Somchem S361
<<locked>>
81%
41814
66%
**48
95%
Somchem S365
<<locked>>
81%
43598
68%
**36
100%
Somchem S385
<<locked>>
81%
39595
62%
**44
97%
Vihtavuori N135
<<locked>>
81%
52895
83%
**30
100%
Vihtavuori N150
<<locked>>
81%
46949
74%
**90
100%
Vihtavuori N160
<<locked>>
81%
50125
79%
**98
100%
Vihtavuori N165
<<locked>>
81%
33257
52%
**00
95%
Vihtavuori N550
<<locked>>
81%
50676
79%
**48
100%
Vihtavuori N555
<<locked>>
81%
38261
60%
**54
100%
[Vihtavuori N560]*
<<locked>>
81%
35534
56%
**21
93%
[Vihtavuori N565]*
<<locked>>
81%
30501
48%
**90
90%
[Vihtavuori N568]*
<<locked>>
89%
34171
54%
**15
90%
Winchester 6.5 StaBALL
<<locked>>
81%
47195
74%
**36
100%
Winchester 760
<<locked>>
81%
53461
84%
**10
100%
Winchester StaBALL HD
<<locked>>
81%
29588
46%
**95
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.

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