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Load data for 7.21 Firebird (Lazzeroni) + .284 | 175gr | Speer Grand Slam

Recommended Powder(s): ADI AR 2218, Alliant Reloder-33, Alliant Reloder-50, IMR 8133 Enduron, Vihtavuori N570

7.21 Firebird (Lazzeroni) + .284 | 175gr | Speer Grand Slam

Load Specifications

(Use the Personalized Load Calculator below to adjust )

Bullet:
.284 | 175gr | Speer Grand Slam
Manufacturer SKU:
1643
Bullet Weight:
175gr | 11.3g
Bullet Diameter:
0.284" | 7.21mm
Bullet Length:
1.270" | 32.3mm
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:
0.573" | 14.6mm
Shank Seated Depth:
0.573" | 14.6mm
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_B6133_C1103
Last updated:
2025-02-02

Load data for 62 loads in caliber 7.21 Firebird (Lazzeroni) with .284 | 175gr | Speer Grand Slam bullet and 31 powders such as ADI AR 2218, Alliant Reloder-33, Alliant Reloder-50, IMR 8133 Enduron, 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 2217
<<locked>>
90%
59915
90%
**46
100%
ADI AR 2218 👍
<<locked>>
93%
59292
89%
**54
100%
ADI AR 2225
<<locked>>
91%
59857
90%
**66
100%
Accurate 8700
<<locked>>
97%
55535
83%
**94
99%
Alliant Reloder-25
<<locked>>
86%
59959
90%
**23
100%
Alliant Reloder-33 👍
<<locked>>
90%
59988
90%
**05
100%
Alliant Reloder-50 👍
<<locked>>
94%
60002
90%
**02
99%
[Hodgdon 50BMG]*
<<locked>>
97%
59016
88%
**59
93%
Hodgdon H1000
<<locked>>
90%
59915
90%
**46
100%
Hodgdon H4831
<<locked>>
85%
59611
89%
**13
100%
Hodgdon Retumbo
<<locked>>
91%
59857
90%
**66
100%
Hodgdon US 869
<<locked>>
97%
59611
89%
**53
96%
Hodgdon TrailBoss
<<locked>>
97%
36825
55%
**60
100%
IMR 4955 Enduron
<<locked>>
83%
59698
89%
**97
100%
IMR 7977 Enduron
<<locked>>
88%
59901
90%
**90
98%
IMR 8133 Enduron 👍
<<locked>>
94%
59930
90%
**66
100%
Lovex D100
<<locked>>
91%
59973
90%
**10
97%
Lovex S071
<<locked>>
87%
59901
90%
**51
100%
Norma 217
<<locked>>
93%
60017
90%
**66
100%
Ramshot LRT
<<locked>>
93%
59756
90%
**12
97%
ReloadSwiss RS 14
<<locked>>
97%
37869
57%
**03
100%
ReloadSwiss RS 76
<<locked>>
85%
59393
89%
**76
100%
ReloadSwiss RS 80
<<locked>>
88%
59872
90%
**82
100%
SNPE Vectan SP 13
<<locked>>
97%
56913
85%
**90
99%
Vihtavuori 20N29
<<locked>>
97%
55651
83%
**94
97%
Vihtavuori 24N41
<<locked>>
93%
59683
89%
**59
96%
Vihtavuori N165
<<locked>>
85%
59770
90%
**61
100%
Vihtavuori N170
<<locked>>
92%
59683
89%
**23
99%
Vihtavuori N565
<<locked>>
85%
59553
89%
**49
100%
Vihtavuori N568
<<locked>>
88%
59973
90%
**92
100%
Vihtavuori N570 👍
<<locked>>
88%
60031
90%
**31
100%

Max Load - Barrel Length: 23.60''

Powder
Charge
FR
MaxP
%
V(0)
z
ADI AR 2217
<<locked>>
81%
43990
66%
**84
100%
[ADI AR 2218]*
<<locked>>
81%
37898
57%
**25
94%
ADI AR 2225
<<locked>>
81%
41510
62%
**67
100%
[Accurate 8700]*
<<locked>>
81%
31125
47%
**82
90%
Alliant Reloder-25
<<locked>>
81%
50908
76%
**99
100%
Alliant Reloder-33
<<locked>>
81%
42743
64%
**94
96%
[Alliant Reloder-50]*
<<locked>>
81%
37492
56%
**59
93%
[Hodgdon 50BMG]*
<<locked>>
92%
49806
75%
**99
90%
Hodgdon H1000
<<locked>>
81%
43990
66%
**84
100%
Hodgdon H4831
<<locked>>
81%
52837
79%
**15
100%
Hodgdon Retumbo
<<locked>>
81%
41510
62%
**67
100%
[Hodgdon US 869]*
<<locked>>
86%
40538
61%
**95
90%
Hodgdon TrailBoss
<<locked>>
81%
29298
44%
**99
100%
IMR 4955 Enduron
<<locked>>
81%
55796
84%
**41
100%
IMR 7977 Enduron
<<locked>>
81%
47790
72%
**80
95%
IMR 8133 Enduron
<<locked>>
81%
38450
58%
**82
98%
[Lovex D100]*
<<locked>>
81%
42409
64%
**95
92%
Lovex S071
<<locked>>
81%
50111
75%
**03
100%
Norma 217
<<locked>>
81%
39508
59%
**12
100%
[Ramshot LRT]*
<<locked>>
83%
40611
61%
**44
90%
ReloadSwiss RS 14
<<locked>>
81%
30284
45%
**45
100%
ReloadSwiss RS 76
<<locked>>
81%
51343
77%
**61
100%
ReloadSwiss RS 80
<<locked>>
81%
46891
70%
**69
99%
[SNPE Vectan SP 13]*
<<locked>>
81%
33011
49%
**11
91%
[Vihtavuori 20N29]*
<<locked>>
85%
35853
54%
**87
90%
[Vihtavuori 24N41]*
<<locked>>
83%
40973
61%
**18
90%
Vihtavuori N165
<<locked>>
81%
53200
80%
**69
100%
Vihtavuori N170
<<locked>>
81%
41249
62%
**85
95%
Vihtavuori N565
<<locked>>
81%
52388
79%
**31
100%
Vihtavuori N568
<<locked>>
81%
47543
71%
**85
99%
Vihtavuori N570
<<locked>>
81%
45934
69%
**76
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.

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