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Load data for .300 Rem. Ultra Mag + .308 | 150gr Hornady ECX

Recommended Powder(s): Alliant Reloder-26, Hodgdon H4350, Norma MRP, Somchem S385, Winchester StaBALL HD

.300 Rem. Ultra Mag + .308 | 150gr Hornady ECX

Load Specifications

(Use the Personalized Load Calculator below to adjust )

Bullet:
.308 | 150gr Hornady ECX
Manufacturer SKU:
30372
Bullet Weight:
150gr | 9.7g
Bullet Diameter:
0.308" | 7.82mm
Bullet Length:
1.200" | 30.5mm
Caliber:
.300 Rem. Ultra Mag load data
Case Length (l3):
2.850" | 72.4mm
Cartridge Length (C.O.L.):
3.238" | 82.3mm
Seated Depth:
0.812" | 20.6mm
Shank Seated Depth:
0.812" | 20.6mm
Case Capacity:
112.5 Grains of Water | 7.30 cm³
Primer Size:
Large Rifle Magnum (LRM)
Max. allowed Pressure:
64977 psi | 4480 bar
LID:
LID_B1382_C374
Last updated:
2025-01-01

Load data for 144 loads in caliber .300 Rem. Ultra Mag with .308 | 150gr Hornady ECX bullet and 72 powders such as Alliant Reloder-26, Hodgdon H4350, Norma MRP, Somchem S385, 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 2208
<<locked>>
83%
58218
90%
**31
100%
ADI AR 2209
<<locked>>
93%
58291
90%
**10
99%
ADI AR 2213
<<locked>>
96%
58146
89%
**33
98%
ADI AR 2217
<<locked>>
97%
43714
67%
**58
95%
ADI AR 2225
<<locked>>
97%
38725
60%
**05
97%
Accurate 2700
<<locked>>
84%
58392
90%
**92
99%
Accurate 3100
<<locked>>
96%
58262
90%
**45
100%
Accurate 4350
<<locked>>
87%
57885
89%
**74
100%
Accurate MAGPRO
<<locked>>
96%
58044
89%
**30
97%
Alliant Reloder-16
<<locked>>
89%
58436
90%
**23
100%
Alliant Reloder-17
<<locked>>
84%
57986
89%
**14
100%
Alliant Reloder-19
<<locked>>
93%
58073
89%
**97
99%
Alliant Reloder-22
<<locked>>
96%
57783
89%
**30
99%
Alliant Reloder-23
<<locked>>
97%
56376
87%
**74
100%
Alliant Reloder-25
<<locked>>
97%
49168
76%
**15
100%
Alliant Reloder-26 👍
<<locked>>
93%
58204
90%
**73
100%
Hodgdon H1000
<<locked>>
97%
43714
67%
**58
95%
Hodgdon H414
<<locked>>
84%
58015
89%
**00
100%
Hodgdon H4350 👍
<<locked>>
91%
58334
90%
**58
100%
Hodgdon H4831
<<locked>>
97%
54984
85%
**28
97%
Hodgdon H4831 SC
<<locked>>
95%
57972
89%
**74
98%
Hodgdon Hybrid 100V
<<locked>>
91%
57972
89%
**35
100%
Hodgdon LVR
<<locked>>
86%
58276
90%
**87
100%
Hodgdon Retumbo
<<locked>>
97%
38725
60%
**05
97%
Hodgdon Superperformance
<<locked>>
86%
58030
89%
**14
100%
Hodgdon VARGET
<<locked>>
83%
58218
90%
**31
100%
Hodgdon TrailBoss
<<locked>>
97%
35244
54%
**52
100%
IMR 4064
<<locked>>
84%
58233
90%
**28
100%
IMR 4166 Enduron
<<locked>>
85%
58160
90%
**31
100%
IMR 4350
<<locked>>
89%
58088
89%
**48
100%
IMR 4451 Enduron
<<locked>>
86%
58305
90%
**48
100%
IMR 4831
<<locked>>
93%
57783
89%
**48
100%
IMR 4955 Enduron
<<locked>>
96%
58363
90%
**51
98%
IMR 7828 SSC
<<locked>>
95%
57841
89%
**46
98%
Lovex S065
<<locked>>
87%
58363
90%
**38
100%
Lovex S070
<<locked>>
88%
58247
90%
**51
100%
Lovex S071
<<locked>>
97%
49385
76%
**10
99%
Norma 204
<<locked>>
89%
58189
90%
**87
99%
[Norma 217]*
<<locked>>
97%
34592
53%
**17
94%
Norma MRP 👍
<<locked>>
94%
58160
90%
**63
100%
Norma URP
<<locked>>
89%
58334
90%
**81
100%
Ramshot Hunter
<<locked>>
89%
58291
90%
**00
100%
Ramshot Magnum
<<locked>>
96%
58160
90%
**07
100%
ReloadSwiss RS 14
<<locked>>
96%
35795
55%
**95
100%
ReloadSwiss RS 60
<<locked>>
85%
58102
89%
**40
100%
ReloadSwiss RS 62
<<locked>>
88%
58436
90%
**94
100%
ReloadSwiss RS 70
<<locked>>
88%
57841
89%
**40
100%
ReloadSwiss RS 76
<<locked>>
97%
48733
75%
**54
99%
[ReloadSwiss RS 80]*
<<locked>>
97%
43700
67%
**13
94%
Rottweil R 903
<<locked>>
84%
58363
90%
**35
100%
Rottweil R 904
<<locked>>
92%
57740
89%
**51
98%
Rottweil R 905
<<locked>>
94%
57885
89%
**94
99%
Rottweil R 907
<<locked>>
86%
58117
89%
**35
100%
SNPE Vectan Tubal 5000
<<locked>>
84%
57754
89%
**00
100%
SNPE Vectan Tubal 7000
<<locked>>
87%
57899
89%
**89
100%
Shooters World Long Rifle
<<locked>>
87%
58363
90%
**38
100%
Somchem S355
<<locked>>
84%
58030
89%
**31
100%
Somchem S361
<<locked>>
91%
58117
89%
**15
98%
Somchem S365
<<locked>>
90%
58363
90%
**77
100%
Somchem S385 👍
<<locked>>
93%
58378
90%
**61
100%
Vihtavuori N135
<<locked>>
85%
57798
89%
**33
100%
Vihtavuori N150
<<locked>>
89%
58059
89%
**82
100%
Vihtavuori N160
<<locked>>
86%
57943
89%
**35
100%
Vihtavuori N165
<<locked>>
97%
55042
85%
**92
99%
Vihtavuori N550
<<locked>>
86%
57914
89%
**84
100%
Vihtavuori N555
<<locked>>
95%
58450
90%
**94
100%
Vihtavuori N560
<<locked>>
96%
57914
89%
**59
98%
Vihtavuori N565
<<locked>>
97%
51184
79%
**18
97%
[Vihtavuori N568]*
<<locked>>
97%
44976
69%
**27
93%
Winchester 6.5 StaBALL
<<locked>>
87%
57783
89%
**99
100%
Winchester 760
<<locked>>
84%
58015
89%
**00
100%
Winchester StaBALL HD 👍
<<locked>>
97%
53838
83%
**50
100%

Max Load - Barrel Length: 23.60''

Powder
Charge
FR
MaxP
%
V(0)
z
ADI AR 2208
<<locked>>
81%
54505
84%
**76
100%
[ADI AR 2209]*
<<locked>>
81%
38566
59%
**46
94%
[ADI AR 2213]*
<<locked>>
81%
34592
53%
**57
90%
[ADI AR 2217]*
<<locked>>
90%
34229
53%
**25
90%
[ADI AR 2225]*
<<locked>>
87%
28689
44%
**07
90%
Accurate 2700
<<locked>>
81%
52866
81%
**10
99%
Accurate 3100
<<locked>>
81%
34316
53%
**05
96%
Accurate 4350
<<locked>>
81%
46050
71%
**77
100%
[Accurate MAGPRO]*
<<locked>>
85%
37971
58%
**53
90%
Alliant Reloder-16
<<locked>>
81%
44077
68%
**97
100%
Alliant Reloder-17
<<locked>>
81%
51329
79%
**15
100%
[Alliant Reloder-19]*
<<locked>>
81%
38406
59%
**40
94%
[Alliant Reloder-22]*
<<locked>>
81%
34374
53%
**64
93%
Alliant Reloder-23
<<locked>>
81%
32750
50%
**35
99%
[Alliant Reloder-25]*
<<locked>>
81%
28790
44%
**23
93%
Alliant Reloder-26
<<locked>>
81%
36201
56%
**76
98%
[Hodgdon H1000]*
<<locked>>
90%
34229
53%
**25
90%
Hodgdon H414
<<locked>>
81%
52243
80%
**09
99%
Hodgdon H4350
<<locked>>
81%
42206
65%
**69
97%
[Hodgdon H4831]*
<<locked>>
83%
35099
54%
**28
90%
[Hodgdon H4831 SC]*
<<locked>>
81%
36143
56%
**57
91%
Hodgdon Hybrid 100V
<<locked>>
81%
41655
64%
**69
100%
Hodgdon LVR
<<locked>>
81%
48327
74%
**30
100%
[Hodgdon Retumbo]*
<<locked>>
87%
28689
44%
**07
90%
Hodgdon Superperformance
<<locked>>
81%
48051
74%
**53
98%
Hodgdon VARGET
<<locked>>
81%
53795
83%
**63
100%
Hodgdon TrailBoss
<<locked>>
81%
28108
43%
**98
100%
IMR 4064
<<locked>>
81%
53185
82%
**56
100%
IMR 4166 Enduron
<<locked>>
81%
52098
80%
**30
99%
IMR 4350
<<locked>>
81%
44367
68%
**18
97%
IMR 4451 Enduron
<<locked>>
81%
50575
78%
**17
99%
IMR 4831
<<locked>>
81%
39813
61%
**46
99%
[IMR 4955 Enduron]*
<<locked>>
81%
36463
56%
**35
91%
[IMR 7828 SSC]*
<<locked>>
81%
35128
54%
**84
91%
Lovex S065
<<locked>>
81%
47863
74%
**67
99%
Lovex S070
<<locked>>
81%
46093
71%
**54
98%
[Lovex S071]*
<<locked>>
81%
29472
45%
**80
94%
Norma 204
<<locked>>
81%
44570
69%
**48
96%
[Norma 217]*
<<locked>>
91%
28732
44%
**43
90%
Norma MRP
<<locked>>
81%
35897
55%
**33
95%
Norma URP
<<locked>>
81%
45165
70%
**67
100%
Ramshot Hunter
<<locked>>
81%
44295
68%
**61
99%
[Ramshot Magnum]*
<<locked>>
81%
31821
49%
**82
92%
ReloadSwiss RS 14
<<locked>>
81%
28703
44%
**37
100%
ReloadSwiss RS 60
<<locked>>
81%
49574
76%
**09
100%
ReloadSwiss RS 62
<<locked>>
81%
46282
71%
**00
100%
ReloadSwiss RS 70
<<locked>>
81%
44498
68%
**13
99%
[ReloadSwiss RS 76]*
<<locked>>
83%
28834
44%
**39
90%
[ReloadSwiss RS 80]*
<<locked>>
92%
36492
56%
**46
90%
Rottweil R 903
<<locked>>
81%
53200
82%
**63
100%
[Rottweil R 904]*
<<locked>>
81%
39929
61%
**30
94%
[Rottweil R 905]*
<<locked>>
81%
37826
58%
**20
94%
Rottweil R 907
<<locked>>
81%
49168
76%
**97
98%
SNPE Vectan Tubal 5000
<<locked>>
81%
53432
82%
**48
100%
SNPE Vectan Tubal 7000
<<locked>>
81%
47210
73%
**08
98%
Shooters World Long Rifle
<<locked>>
81%
47863
74%
**67
99%
Somchem S355
<<locked>>
81%
53069
82%
**56
100%
[Somchem S361]*
<<locked>>
81%
40828
63%
**03
93%
Somchem S365
<<locked>>
81%
42119
65%
**25
100%
Somchem S385
<<locked>>
81%
38522
59%
**10
96%
Vihtavuori N135
<<locked>>
81%
51503
79%
**51
100%
Vihtavuori N150
<<locked>>
81%
45658
70%
**95
100%
Vihtavuori N160
<<locked>>
81%
48849
75%
**97
100%
[Vihtavuori N165]*
<<locked>>
81%
32184
50%
**46
92%
Vihtavuori N550
<<locked>>
81%
49559
76%
**53
100%
Vihtavuori N555
<<locked>>
81%
36912
57%
**26
99%
[Vihtavuori N560]*
<<locked>>
81%
34896
54%
**90
90%
[Vihtavuori N565]*
<<locked>>
85%
33939
52%
**44
90%
[Vihtavuori N568]*
<<locked>>
92%
38203
59%
**82
90%
Winchester 6.5 StaBALL
<<locked>>
81%
46209
71%
**22
100%
Winchester 760
<<locked>>
81%
52243
80%
**09
99%
Winchester StaBALL HD
<<locked>>
81%
28195
43%
**35
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.

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