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Load data for 7.21 Firebird (Lazzeroni) + .284 | 154gr | Hornady SST InterLock

Recommended Powder(s): ADI AR 2217, Hodgdon H1000, Norma 217, ReloadSwiss RS 80, Vihtavuori N568

7.21 Firebird (Lazzeroni) + .284 | 154gr | Hornady SST InterLock

Load Specifications

(Use the Personalized Load Calculator below to adjust )

Bullet:
.284 | 154gr | Hornady SST InterLock
Manufacturer SKU:
28302
Bullet Weight:
154gr | 10.0g
Bullet Diameter:
0.284" | 7.21mm
Bullet Length:
1.340" | 34.0mm
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:
0.643" | 16.3mm
Shank Seated Depth:
0.523" | 13.3mm
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_B2634_C1103
Last updated:
2025-02-02
Recommended Twist Rate:
1:10 - 1:9

Load data for 80 loads in caliber 7.21 Firebird (Lazzeroni) with .284 | 154gr | Hornady SST InterLock bullet and 40 powders such as ADI AR 2217, Hodgdon H1000, Norma 217, ReloadSwiss RS 80, Vihtavuori N568. 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>>
85%
59973
90%
**27
100%
ADI AR 2217 👍
<<locked>>
93%
59915
90%
**10
100%
ADI AR 2218
<<locked>>
96%
59901
90%
**28
99%
ADI AR 2225
<<locked>>
95%
59799
90%
**23
100%
Accurate 3100
<<locked>>
85%
59480
89%
**09
100%
Accurate 8700
<<locked>>
97%
48965
73%
**27
96%
Accurate MAGPRO
<<locked>>
84%
59625
89%
**33
100%
Alliant Reloder-22
<<locked>>
85%
59857
90%
**04
100%
Alliant Reloder-23
<<locked>>
86%
59872
90%
**28
100%
Alliant Reloder-25
<<locked>>
89%
59799
90%
**94
100%
Alliant Reloder-33
<<locked>>
93%
59480
89%
**50
99%
Alliant Reloder-50
<<locked>>
97%
59538
89%
**43
99%
Hodgdon H1000 👍
<<locked>>
93%
59915
90%
**10
100%
Hodgdon H4831
<<locked>>
88%
59741
90%
**71
100%
Hodgdon H4831 SC
<<locked>>
84%
59930
90%
**81
100%
Hodgdon Retumbo
<<locked>>
95%
59799
90%
**23
100%
[Hodgdon US 869]*
<<locked>>
97%
53548
80%
**89
93%
Hodgdon TrailBoss
<<locked>>
96%
36274
54%
**62
100%
IMR 4955 Enduron
<<locked>>
86%
59567
89%
**41
100%
IMR 7828 SSC
<<locked>>
84%
59654
89%
**27
100%
IMR 7977 Enduron
<<locked>>
90%
59799
90%
**18
96%
IMR 8133 Enduron
<<locked>>
97%
58262
87%
**07
100%
Lovex D100
<<locked>>
93%
59596
89%
**38
95%
Lovex S071
<<locked>>
90%
59814
90%
**09
100%
Norma 217 👍
<<locked>>
97%
59872
90%
**33
100%
Ramshot LRT
<<locked>>
97%
60002
90%
**53
95%
Ramshot Magnum
<<locked>>
85%
59828
90%
**74
100%
ReloadSwiss RS 14
<<locked>>
97%
37521
56%
**08
100%
ReloadSwiss RS 76
<<locked>>
88%
59843
90%
**53
100%
ReloadSwiss RS 80 👍
<<locked>>
91%
59611
89%
**43
100%
SNPE Vectan SP 13
<<locked>>
97%
50386
76%
**30
96%
[Vihtavuori 20N29]*
<<locked>>
97%
49052
74%
**07
94%
Vihtavuori 24N41
<<locked>>
96%
59770
90%
**07
95%
Vihtavuori N165
<<locked>>
87%
59901
90%
**22
100%
Vihtavuori N170
<<locked>>
96%
59973
90%
**64
98%
Vihtavuori N560
<<locked>>
84%
59814
90%
**36
100%
Vihtavuori N565
<<locked>>
88%
59814
90%
**04
100%
Vihtavuori N568 👍
<<locked>>
91%
59973
90%
**53
100%
Vihtavuori N570
<<locked>>
92%
59669
89%
**79
99%
Winchester StaBALL HD
<<locked>>
84%
59770
90%
**94
100%

Max Load - Barrel Length: 23.60''

Powder
Charge
FR
MaxP
%
V(0)
z
ADI AR 2213
<<locked>>
81%
52344
78%
**99
100%
ADI AR 2217
<<locked>>
81%
39233
59%
**26
97%
[ADI AR 2218]*
<<locked>>
82%
35099
53%
**64
90%
ADI AR 2225
<<locked>>
81%
36448
55%
**00
99%
Accurate 3100
<<locked>>
81%
52707
79%
**00
100%
[Accurate 8700]*
<<locked>>
87%
34330
51%
**92
90%
Accurate MAGPRO
<<locked>>
81%
52866
79%
**12
99%
Alliant Reloder-22
<<locked>>
81%
52982
79%
**02
100%
Alliant Reloder-23
<<locked>>
81%
51605
77%
**13
100%
Alliant Reloder-25
<<locked>>
81%
45585
68%
**61
100%
[Alliant Reloder-33]*
<<locked>>
81%
37463
56%
**10
92%
[Alliant Reloder-50]*
<<locked>>
83%
35230
53%
**31
90%
Hodgdon H1000
<<locked>>
81%
39233
59%
**26
97%
Hodgdon H4831
<<locked>>
81%
48225
72%
**74
99%
Hodgdon H4831 SC
<<locked>>
81%
53751
81%
**72
99%
Hodgdon Retumbo
<<locked>>
81%
36448
55%
**00
99%
[Hodgdon US 869]*
<<locked>>
92%
45469
68%
**28
90%
Hodgdon TrailBoss
<<locked>>
81%
29138
44%
**01
100%
IMR 4955 Enduron
<<locked>>
81%
51474
77%
**13
99%
IMR 7828 SSC
<<locked>>
81%
54476
82%
**35
100%
[IMR 7977 Enduron]*
<<locked>>
81%
43918
66%
**26
92%
IMR 8133 Enduron
<<locked>>
81%
33910
51%
**08
95%
[Lovex D100]*
<<locked>>
84%
43178
65%
**40
90%
Lovex S071
<<locked>>
81%
45484
68%
**79
100%
Norma 217
<<locked>>
81%
34577
52%
**35
98%
[Ramshot LRT]*
<<locked>>
89%
44976
67%
**77
90%
Ramshot Magnum
<<locked>>
81%
52040
78%
**46
100%
ReloadSwiss RS 14
<<locked>>
81%
29892
45%
**41
100%
ReloadSwiss RS 76
<<locked>>
81%
44947
67%
**07
100%
ReloadSwiss RS 80
<<locked>>
81%
41147
62%
**95
97%
[SNPE Vectan SP 13]*
<<locked>>
86%
35201
53%
**85
90%
[Vihtavuori 20N29]*
<<locked>>
91%
39711
60%
**13
90%
[Vihtavuori 24N41]*
<<locked>>
89%
45295
68%
**44
90%
Vihtavuori N165
<<locked>>
81%
48559
73%
**48
100%
[Vihtavuori N170]*
<<locked>>
81%
37347
56%
**15
91%
Vihtavuori N560
<<locked>>
81%
53548
80%
**35
100%
Vihtavuori N565
<<locked>>
81%
47007
70%
**87
99%
Vihtavuori N568
<<locked>>
81%
42018
63%
**05
96%
[Vihtavuori N570]*
<<locked>>
81%
40408
61%
**99
93%
Winchester StaBALL HD
<<locked>>
81%
52257
78%
**86
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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