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Load data for 7.21 Firebird (Lazzeroni) + .284 | 139gr | Hornady GMX

Recommended Powder(s):

7.21 Firebird (Lazzeroni) + .284 | 139gr | Hornady GMX

Load Specifications

(Use the Personalized Load Calculator below to adjust )

Bullet:
.284 | 139gr | Hornady GMX
Manufacturer SKU:
28270
Bullet Weight:
139gr | 9.0g
Bullet Diameter:
0.284" | 7.21mm
Bullet Length:
1.380" | 35.1mm
Caliber:
7.21 Firebird (Lazzeroni) load data
Case Length (l3):
2.800" | 71.1mm
Cartridge Length (C.O.L.):
3.497" | 88.8mm
Seated Depth:
0.683" | 17.4mm
Shank Seated Depth:
0.563" | 14.3mm
Case Capacity:
121.0 Grains of Water | 7.86 cm³
Primer Size:
Large Rifle Magnum (LRM)
Max. allowed Pressure:
66717 psi | 4600 bar
LID:
LID_B2626_C1103
Last updated:
2025-01-01
Recommended Twist Rate:
1:10 - 1:8

Load data for 96 loads in caliber 7.21 Firebird (Lazzeroni) with .284 | 139gr | Hornady GMX bullet and 48 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
ADI AR 2209
<<locked>>
84%
59683
89%
**19
100%
ADI AR 2213
<<locked>>
87%
59901
90%
**48
100%
ADI AR 2217 👍
<<locked>>
95%
59625
89%
**28
100%
ADI AR 2218
<<locked>>
97%
55317
83%
**71
98%
ADI AR 2225 👍
<<locked>>
97%
58262
87%
**45
100%
Accurate 3100
<<locked>>
87%
59669
89%
**40
100%
[Accurate 8700]*
<<locked>>
97%
44599
67%
**40
94%
Accurate MAGPRO
<<locked>>
87%
59756
90%
**48
99%
Alliant Reloder-19
<<locked>>
85%
59712
90%
**15
100%
Alliant Reloder-22
<<locked>>
87%
59843
90%
**28
100%
Alliant Reloder-23
<<locked>>
88%
59857
90%
**63
100%
Alliant Reloder-25
<<locked>>
91%
60002
90%
**28
100%
Alliant Reloder-33
<<locked>>
96%
59857
90%
**81
98%
Alliant Reloder-50
<<locked>>
97%
54114
81%
**66
97%
Hodgdon H1000 👍
<<locked>>
95%
59625
89%
**28
100%
Hodgdon H4350
<<locked>>
83%
59944
90%
**59
100%
Hodgdon H4831
<<locked>>
90%
59959
90%
**05
100%
Hodgdon H4831 SC
<<locked>>
86%
59654
89%
**92
100%
Hodgdon Retumbo 👍
<<locked>>
97%
58262
87%
**45
100%
Hodgdon TrailBoss
<<locked>>
96%
36100
54%
**47
100%
IMR 4831
<<locked>>
84%
60046
90%
**43
100%
IMR 4955 Enduron
<<locked>>
88%
60002
90%
**76
100%
IMR 7828 SSC
<<locked>>
86%
59480
89%
**45
100%
IMR 7977 Enduron
<<locked>>
92%
59625
89%
**30
95%
IMR 8133 Enduron
<<locked>>
97%
53417
80%
**59
99%
[Lovex D100]*
<<locked>>
96%
59988
90%
**56
94%
Lovex S071
<<locked>>
92%
60017
90%
**40
100%
Norma 217
<<locked>>
97%
54781
82%
**79
100%
Norma MRP
<<locked>>
84%
59495
89%
**38
100%
[Ramshot LRT]*
<<locked>>
97%
55535
83%
**89
92%
Ramshot Magnum
<<locked>>
87%
59785
90%
**99
100%
ReloadSwiss RS 14
<<locked>>
97%
37289
56%
**00
100%
ReloadSwiss RS 76
<<locked>>
91%
59857
90%
**01
100%
ReloadSwiss RS 80
<<locked>>
93%
59350
89%
**71
99%
Rottweil R 904
<<locked>>
84%
59799
90%
**86
100%
Rottweil R 905
<<locked>>
85%
59698
89%
**02
100%
[SNPE Vectan SP 13]*
<<locked>>
97%
46775
70%
**59
94%
Somchem S361
<<locked>>
83%
59567
89%
**40
100%
Somchem S385
<<locked>>
85%
60031
90%
**73
100%
[Vihtavuori 24N41]*
<<locked>>
97%
55927
84%
**50
92%
Vihtavuori N165
<<locked>>
89%
59379
89%
**46
100%
Vihtavuori N170
<<locked>>
97%
58233
87%
**56
97%
Vihtavuori N555
<<locked>>
85%
60017
90%
**73
100%
Vihtavuori N560
<<locked>>
87%
59973
90%
**71
100%
Vihtavuori N565 👍
<<locked>>
90%
59495
89%
**25
100%
Vihtavuori N568
<<locked>>
93%
59741
90%
**71
99%
Vihtavuori N570
<<locked>>
94%
59553
89%
**01
98%
Winchester StaBALL HD
<<locked>>
87%
59712
90%
**45
100%

Max Load - Barrel Length: 23.60''

Powder
Charge
FR
MaxP
%
V(0)
z
ADI AR 2209
<<locked>>
81%
53301
80%
**10
100%
ADI AR 2213
<<locked>>
81%
48602
73%
**48
98%
ADI AR 2217
<<locked>>
81%
36100
54%
**53
95%
[ADI AR 2218]*
<<locked>>
87%
38189
57%
**54
90%
ADI AR 2225
<<locked>>
81%
33388
50%
**23
97%
Accurate 3100
<<locked>>
81%
49153
74%
**63
100%
[Accurate 8700]*
<<locked>>
92%
37521
56%
**69
90%
Accurate MAGPRO
<<locked>>
81%
48660
73%
**48
97%
Alliant Reloder-19
<<locked>>
81%
53127
80%
**07
100%
Alliant Reloder-22
<<locked>>
81%
49298
74%
**58
99%
Alliant Reloder-23
<<locked>>
81%
47688
71%
**79
100%
Alliant Reloder-25
<<locked>>
81%
41872
63%
**10
100%
[Alliant Reloder-33]*
<<locked>>
83%
36332
54%
**82
90%
[Alliant Reloder-50]*
<<locked>>
87%
37652
56%
**12
90%
Hodgdon H1000
<<locked>>
81%
36100
54%
**53
95%
Hodgdon H4350
<<locked>>
81%
55927
84%
**94
100%
Hodgdon H4831
<<locked>>
81%
44947
67%
**23
97%
Hodgdon H4831 SC
<<locked>>
81%
50096
75%
**22
98%
Hodgdon Retumbo
<<locked>>
81%
33388
50%
**23
97%
Hodgdon TrailBoss
<<locked>>
81%
28964
43%
**83
100%
IMR 4831
<<locked>>
81%
54462
82%
**61
100%
IMR 4955 Enduron
<<locked>>
81%
48486
73%
**76
98%
IMR 7828 SSC
<<locked>>
81%
50270
75%
**94
99%
[IMR 7977 Enduron]*
<<locked>>
83%
43323
65%
**18
90%
[IMR 8133 Enduron]*
<<locked>>
81%
30806
46%
**21
92%
[Lovex D100]*
<<locked>>
89%
47282
71%
**27
90%
Lovex S071
<<locked>>
81%
42293
63%
**31
100%
Norma 217
<<locked>>
81%
31198
47%
**61
95%
Norma MRP
<<locked>>
81%
52620
79%
**20
100%
[Ramshot LRT]*
<<locked>>
94%
49516
74%
**77
90%
Ramshot Magnum
<<locked>>
81%
47572
71%
**89
100%
ReloadSwiss RS 14
<<locked>>
81%
29675
44%
**26
100%
ReloadSwiss RS 76
<<locked>>
81%
40567
61%
**33
99%
[ReloadSwiss RS 80]*
<<locked>>
81%
37478
56%
**12
94%
Rottweil R 904
<<locked>>
81%
53621
80%
**71
99%
Rottweil R 905
<<locked>>
81%
52924
79%
**91
100%
[SNPE Vectan SP 13]*
<<locked>>
91%
37811
57%
**62
90%
Somchem S361
<<locked>>
81%
55187
83%
**61
99%
Somchem S385
<<locked>>
81%
53214
80%
**61
100%
[Vihtavuori 24N41]*
<<locked>>
94%
49734
75%
**35
90%
Vihtavuori N165
<<locked>>
81%
45237
68%
**04
99%
[Vihtavuori N170]*
<<locked>>
85%
39059
59%
**62
90%
Vihtavuori N555
<<locked>>
81%
52736
79%
**58
100%
Vihtavuori N560
<<locked>>
81%
49371
74%
**81
98%
Vihtavuori N565
<<locked>>
81%
43482
65%
**27
97%
[Vihtavuori N568]*
<<locked>>
81%
38479
58%
**41
94%
[Vihtavuori N570]*
<<locked>>
81%
37202
56%
**28
90%
Winchester StaBALL HD
<<locked>>
81%
47398
71%
**51
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.

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

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