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Load data for 7.21 Firebird (Lazzeroni) + .284 | 175gr | Hornady InterLock RN

Recommended Powder(s):

7.21 Firebird (Lazzeroni) + .284 | 175gr | Hornady InterLock RN

Load Specifications

(Use the Personalized Load Calculator below to adjust )

Bullet:
.284 | 175gr | Hornady InterLock RN
Manufacturer SKU:
2855
Bullet Weight:
175gr | 11.3g
Bullet Diameter:
0.284" | 7.21mm
Bullet Length:
<<locked>>
Caliber:
7.21 Firebird (Lazzeroni) load data
Case Length (l3):
2.800" | 71.1mm
Cartridge Length (C.O.L.):
<<locked>>
Seated Depth:
<<locked>>
Shank Seated Depth:
<<locked>>
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_B2646_C1103
Last updated:
2026-01-22

Load data for 68 loads in caliber 7.21 Firebird (Lazzeroni) with .284 | 175gr | Hornady InterLock RN bullet and 34 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 2217
<<locked>>
90%
59669
89%
**46
100%
ADI AR 2218 👍
<<locked>>
93%
59741
90%
**68
100%
ADI AR 2225
<<locked>>
91%
59901
90%
**63
100%
Accurate 8700
<<locked>>
97%
56101
84%
**00
99%
Alliant Reloder-25
<<locked>>
85%
59553
89%
**27
100%
Alliant Reloder-33 👍
<<locked>>
90%
59770
90%
**02
100%
Alliant Reloder-50 👍
<<locked>>
93%
59843
90%
**99
99%
Baschieri & Pellagri 109
<<locked>>
84%
59727
90%
**23
100%
Bofors RP15
<<locked>>
84%
59727
90%
**36
100%
Bofors RP30
<<locked>>
87%
59524
89%
**49
100%
[Hodgdon 50BMG]*
<<locked>>
97%
59393
89%
**72
93%
Hodgdon H1000
<<locked>>
90%
59669
89%
**46
100%
Hodgdon H4831
<<locked>>
85%
59698
89%
**17
100%
Hodgdon Retumbo
<<locked>>
91%
59901
90%
**63
100%
Hodgdon US 869
<<locked>>
97%
59944
90%
**49
96%
Hodgdon TrailBoss
<<locked>>
97%
36840
55%
**64
100%
IMR 7977 Enduron
<<locked>>
88%
59654
89%
**77
98%
IMR 8133 Enduron 👍
<<locked>>
94%
59756
90%
**66
100%
Lovex D100
<<locked>>
90%
59625
89%
**07
97%
Lovex S071
<<locked>>
86%
59451
89%
**41
100%
Norma 217
<<locked>>
93%
59654
89%
**56
100%
Ramshot LRT
<<locked>>
93%
60031
90%
**18
97%
ReloadSwiss RS 14
<<locked>>
97%
37884
57%
**06
100%
ReloadSwiss RS 76
<<locked>>
85%
59915
90%
**89
100%
ReloadSwiss RS 80
<<locked>>
87%
59814
90%
**82
100%
SNPE Vectan SP 13
<<locked>>
97%
56869
85%
**97
99%
Shooters World 50 BMG
<<locked>>
90%
59625
89%
**07
97%
Vihtavuori 20N29
<<locked>>
97%
55999
84%
**00
98%
Vihtavuori 24N41
<<locked>>
93%
59640
89%
**69
96%
Vihtavuori N165
<<locked>>
84%
59654
89%
**64
100%
Vihtavuori N170
<<locked>>
93%
59988
90%
**20
99%
Vihtavuori N565
<<locked>>
85%
59611
89%
**46
100%
Vihtavuori N568
<<locked>>
87%
59495
89%
**79
100%
Vihtavuori N570 👍
<<locked>>
88%
59553
89%
**15
99%

Max Load - Barrel Length: 23.60''

Powder
Charge
FR
MaxP
%
V(0)
z
ADI AR 2217
<<locked>>
81%
44382
67%
**00
100%
ADI AR 2218
<<locked>>
81%
38290
57%
**44
95%
ADI AR 2225
<<locked>>
81%
41626
62%
**67
100%
[Accurate 8700]*
<<locked>>
81%
31198
47%
**82
90%
Alliant Reloder-25
<<locked>>
81%
51242
77%
**05
100%
Alliant Reloder-33
<<locked>>
81%
43163
65%
**00
96%
[Alliant Reloder-50]*
<<locked>>
81%
37811
57%
**62
94%
Baschieri & Pellagri 109
<<locked>>
81%
54027
81%
**41
99%
Bofors RP15
<<locked>>
81%
54795
82%
**61
100%
Bofors RP30
<<locked>>
81%
47848
72%
**62
100%
[Hodgdon 50BMG]*
<<locked>>
92%
49530
74%
**92
90%
Hodgdon H1000
<<locked>>
81%
44382
67%
**00
100%
Hodgdon H4831
<<locked>>
81%
52953
79%
**15
100%
Hodgdon Retumbo
<<locked>>
81%
41626
62%
**67
100%
[Hodgdon US 869]*
<<locked>>
86%
41162
62%
**08
90%
Hodgdon TrailBoss
<<locked>>
81%
29356
44%
**03
100%
IMR 7977 Enduron
<<locked>>
81%
48196
72%
**84
95%
IMR 8133 Enduron
<<locked>>
81%
38827
58%
**89
98%
[Lovex D100]*
<<locked>>
81%
42786
64%
**98
92%
Lovex S071
<<locked>>
81%
50241
75%
**03
100%
Norma 217
<<locked>>
81%
39639
59%
**12
100%
[Ramshot LRT]*
<<locked>>
83%
40886
61%
**44
90%
ReloadSwiss RS 14
<<locked>>
81%
30342
45%
**45
100%
ReloadSwiss RS 76
<<locked>>
81%
51634
77%
**58
100%
ReloadSwiss RS 80
<<locked>>
81%
47253
71%
**69
99%
[SNPE Vectan SP 13]*
<<locked>>
81%
33083
50%
**11
91%
[Shooters World 50 BMG]*
<<locked>>
81%
42786
64%
**98
92%
[Vihtavuori 20N29]*
<<locked>>
85%
35810
54%
**84
90%
[Vihtavuori 24N41]*
<<locked>>
83%
41031
61%
**18
90%
Vihtavuori N165
<<locked>>
81%
53679
80%
**82
100%
Vihtavuori N170
<<locked>>
81%
41495
62%
**85
95%
Vihtavuori N565
<<locked>>
81%
52576
79%
**31
100%
Vihtavuori N568
<<locked>>
81%
47630
71%
**85
99%
Vihtavuori N570
<<locked>>
81%
46122
69%
**79
97%

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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