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Load data for 7.21 Firebird (Lazzeroni) + .284 | 160gr | Sierra HPBT GameKing

Recommended Powder(s): IMR 8133 Enduron, Norma 217, ReloadSwiss RS 80, Vihtavuori N568, Vihtavuori N570

7.21 Firebird (Lazzeroni) + .284 | 160gr | Sierra HPBT GameKing

Load Specifications

(Use the Personalized Load Calculator below to adjust )

Bullet:
.284 | 160gr | Sierra HPBT GameKing
Manufacturer SKU:
1925
Bullet Weight:
160gr | 10.4g
Bullet Diameter:
0.284" | 7.21mm
Bullet Length:
1.310" | 33.3mm
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:
0.613" | 15.6mm
Shank Seated Depth:
0.473" | 12.0mm
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_B5845_C1103
Last updated:
2025-01-01
Recommended Twist Rate:
1:11 - 1:9

Load data for 78 loads in caliber 7.21 Firebird (Lazzeroni) with .284 | 160gr | Sierra HPBT GameKing bullet and 39 powders such as IMR 8133 Enduron, Norma 217, ReloadSwiss RS 80, Vihtavuori N568, Vihtavuori N570. 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 2213
<<locked>>
84%
59524
89%
**71
100%
ADI AR 2217
<<locked>>
92%
59495
89%
**51
100%
ADI AR 2218
<<locked>>
95%
59654
89%
**86
100%
ADI AR 2225
<<locked>>
94%
59524
89%
**77
100%
Accurate 3100
<<locked>>
84%
59625
89%
**53
100%
Accurate 8700
<<locked>>
97%
50981
76%
**10
97%
Accurate MAGPRO
<<locked>>
84%
59785
90%
**87
100%
Alliant Reloder-22
<<locked>>
83%
59509
89%
**48
100%
Alliant Reloder-23
<<locked>>
84%
59538
89%
**79
100%
Alliant Reloder-25
<<locked>>
88%
59567
89%
**35
100%
Alliant Reloder-33
<<locked>>
92%
59669
89%
**07
99%
Alliant Reloder-50
<<locked>>
96%
59509
89%
**97
99%
Hodgdon H1000
<<locked>>
92%
59495
89%
**51
100%
Hodgdon H4831
<<locked>>
87%
59785
90%
**25
100%
Hodgdon H4831 SC
<<locked>>
83%
59973
90%
**35
100%
Hodgdon Retumbo
<<locked>>
94%
59524
89%
**77
100%
[Hodgdon US 869]*
<<locked>>
97%
56014
84%
**86
94%
Hodgdon TrailBoss
<<locked>>
97%
36680
55%
**39
100%
IMR 4955 Enduron
<<locked>>
85%
59553
89%
**99
100%
IMR 7977 Enduron
<<locked>>
89%
59596
89%
**76
97%
IMR 8133 Enduron 👍
<<locked>>
96%
59886
90%
**84
100%
Lovex D100
<<locked>>
92%
59683
89%
**12
96%
Lovex S071
<<locked>>
88%
59292
89%
**53
100%
Norma 217 👍
<<locked>>
95%
59756
90%
**74
100%
Ramshot LRT
<<locked>>
95%
59495
89%
**14
96%
Ramshot Magnum
<<locked>>
83%
59422
89%
**12
100%
ReloadSwiss RS 14
<<locked>>
97%
37666
56%
**82
100%
ReloadSwiss RS 76
<<locked>>
87%
59712
89%
**07
100%
ReloadSwiss RS 80 👍
<<locked>>
90%
59756
90%
**97
100%
SNPE Vectan SP 13
<<locked>>
97%
52968
79%
**30
97%
Vihtavuori 20N29
<<locked>>
97%
51430
77%
**20
95%
Vihtavuori 24N41
<<locked>>
95%
59393
89%
**71
95%
Vihtavuori N165
<<locked>>
86%
59930
90%
**72
100%
Vihtavuori N170
<<locked>>
94%
59466
89%
**22
98%
Vihtavuori N560
<<locked>>
83%
60017
90%
**94
100%
Vihtavuori N565
<<locked>>
87%
59857
90%
**58
100%
Vihtavuori N568 👍
<<locked>>
90%
59698
89%
**94
100%
Vihtavuori N570 👍
<<locked>>
90%
59466
89%
**36
99%
Winchester StaBALL HD
<<locked>>
83%
59828
90%
**54
100%

Max Load - Barrel Length: 23.60''

Powder
Charge
FR
MaxP
%
V(0)
z
ADI AR 2213
<<locked>>
81%
54215
81%
**79
100%
ADI AR 2217
<<locked>>
81%
40872
61%
**17
98%
[ADI AR 2218]*
<<locked>>
81%
35099
53%
**41
91%
ADI AR 2225
<<locked>>
81%
38072
57%
**94
100%
Accurate 3100
<<locked>>
81%
54505
82%
**87
100%
[Accurate 8700]*
<<locked>>
86%
33620
50%
**36
90%
Accurate MAGPRO
<<locked>>
81%
54723
82%
**05
99%
Alliant Reloder-22
<<locked>>
81%
54839
82%
**79
100%
Alliant Reloder-23
<<locked>>
81%
53476
80%
**87
100%
Alliant Reloder-25
<<locked>>
81%
47456
71%
**54
100%
[Alliant Reloder-33]*
<<locked>>
81%
39378
59%
**23
94%
[Alliant Reloder-50]*
<<locked>>
81%
34360
52%
**75
90%
Hodgdon H1000
<<locked>>
81%
40872
61%
**17
98%
Hodgdon H4831
<<locked>>
81%
49864
75%
**67
99%
Hodgdon H4831 SC
<<locked>>
81%
55477
83%
**63
100%
Hodgdon Retumbo
<<locked>>
81%
38072
57%
**94
100%
[Hodgdon US 869]*
<<locked>>
90%
44034
66%
**59
90%
Hodgdon TrailBoss
<<locked>>
81%
29153
44%
**68
100%
IMR 4955 Enduron
<<locked>>
81%
53026
79%
**90
100%
[IMR 7977 Enduron]*
<<locked>>
81%
45281
68%
**23
93%
IMR 8133 Enduron
<<locked>>
81%
35505
53%
**05
96%
[Lovex D100]*
<<locked>>
83%
42177
63%
**84
90%
Lovex S071
<<locked>>
81%
47065
71%
**59
100%
Norma 217
<<locked>>
81%
36303
54%
**35
98%
[Ramshot LRT]*
<<locked>>
87%
43816
66%
**05
90%
Ramshot Magnum
<<locked>>
81%
54114
81%
**40
100%
ReloadSwiss RS 14
<<locked>>
81%
30110
45%
**18
100%
ReloadSwiss RS 76
<<locked>>
81%
47021
70%
**07
100%
ReloadSwiss RS 80
<<locked>>
81%
43207
65%
**02
98%
[SNPE Vectan SP 13]*
<<locked>>
84%
33765
51%
**20
90%
[Vihtavuori 20N29]*
<<locked>>
89%
38537
58%
**44
90%
[Vihtavuori 24N41]*
<<locked>>
87%
44164
66%
**72
90%
Vihtavuori N165
<<locked>>
81%
50198
75%
**28
100%
[Vihtavuori N170]*
<<locked>>
81%
38725
58%
**18
92%
Vihtavuori N560
<<locked>>
81%
55434
83%
**12
100%
Vihtavuori N565
<<locked>>
81%
49037
74%
**74
99%
Vihtavuori N568
<<locked>>
81%
43874
66%
**12
97%
Vihtavuori N570
<<locked>>
81%
42192
63%
**92
95%
Winchester StaBALL HD
<<locked>>
81%
54897
82%
**76
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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