top of page

Load data for 7.21 Firebird (Lazzeroni) + .284 | 170gr | Sierra RN Prohunter

Recommended Powder(s):

7.21 Firebird (Lazzeroni) + .284 | 170gr | Sierra RN Prohunter

Load Specifications

(Use the Personalized Load Calculator below to adjust )

Bullet:
.284 | 170gr | Sierra RN Prohunter
Manufacturer SKU:
1950
Bullet Weight:
170gr | 11.0g
Bullet Diameter:
0.284" | 7.21mm
Bullet Length:
1.225" | 31.1mm
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:
0.528" | 13.4mm
Shank Seated Depth:
0.528" | 13.4mm
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_B5851_C1103
Last updated:
2025-01-01

Load data for 62 loads in caliber 7.21 Firebird (Lazzeroni) with .284 | 170gr | Sierra RN Prohunter bullet and 31 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".

  • No data yet

  • .

    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%
59611
89%
**82
100%
ADI AR 2218 👍
<<locked>>
93%
59553
89%
**94
100%
ADI AR 2225
<<locked>>
92%
59408
89%
**95
100%
Accurate 8700
<<locked>>
97%
54752
82%
**13
99%
Alliant Reloder-25
<<locked>>
86%
59727
90%
**63
100%
Alliant Reloder-33 👍
<<locked>>
90%
59567
89%
**45
100%
Alliant Reloder-50 👍
<<locked>>
94%
60046
90%
**38
99%
[Hodgdon 50BMG]*
<<locked>>
97%
58059
87%
**82
93%
Hodgdon H1000
<<locked>>
90%
59611
89%
**82
100%
Hodgdon H4831
<<locked>>
85%
59828
90%
**53
100%
Hodgdon Retumbo
<<locked>>
92%
59408
89%
**95
100%
Hodgdon US 869
<<locked>>
97%
59132
89%
**72
96%
Hodgdon TrailBoss
<<locked>>
96%
36492
55%
**80
100%
IMR 4955 Enduron
<<locked>>
83%
59770
90%
**27
100%
IMR 7977 Enduron
<<locked>>
88%
59872
90%
**23
98%
IMR 8133 Enduron 👍
<<locked>>
94%
59524
89%
**95
100%
Lovex D100
<<locked>>
91%
59669
89%
**36
97%
Lovex S071
<<locked>>
87%
59553
89%
**81
100%
Norma 217
<<locked>>
93%
59509
89%
**89
100%
Ramshot LRT
<<locked>>
94%
59901
90%
**45
96%
ReloadSwiss RS 14
<<locked>>
97%
37768
57%
**26
100%
ReloadSwiss RS 76
<<locked>>
85%
59727
90%
**22
100%
ReloadSwiss RS 80
<<locked>>
88%
59654
89%
**15
100%
SNPE Vectan SP 13
<<locked>>
97%
56246
84%
**17
99%
Vihtavuori 20N29
<<locked>>
97%
54781
82%
**00
97%
Vihtavuori 24N41
<<locked>>
94%
59596
89%
**95
96%
Vihtavuori N165
<<locked>>
85%
59756
90%
**00
100%
Vihtavuori N170
<<locked>>
93%
60002
90%
**53
99%
Vihtavuori N565
<<locked>>
85%
59640
89%
**86
100%
Vihtavuori N568
<<locked>>
88%
59886
90%
**22
100%
Vihtavuori N570 👍
<<locked>>
89%
60017
90%
**61
99%

Max Load - Barrel Length: 23.60''

Powder
Charge
FR
MaxP
%
V(0)
z
ADI AR 2217
<<locked>>
81%
43395
65%
**07
99%
[ADI AR 2218]*
<<locked>>
81%
37347
56%
**41
94%
ADI AR 2225
<<locked>>
81%
40741
61%
**74
100%
[Accurate 8700]*
<<locked>>
82%
32024
48%
**31
90%
Alliant Reloder-25
<<locked>>
81%
50328
75%
**18
100%
Alliant Reloder-33
<<locked>>
81%
42061
63%
**10
96%
[Alliant Reloder-50]*
<<locked>>
81%
36869
55%
**72
93%
[Hodgdon 50BMG]*
<<locked>>
93%
50981
76%
**51
90%
Hodgdon H1000
<<locked>>
81%
43395
65%
**07
99%
Hodgdon H4831
<<locked>>
81%
52025
78%
**31
100%
Hodgdon Retumbo
<<locked>>
81%
40741
61%
**74
100%
[Hodgdon US 869]*
<<locked>>
87%
41843
63%
**54
90%
Hodgdon TrailBoss
<<locked>>
81%
29414
44%
**29
100%
IMR 4955 Enduron
<<locked>>
81%
55390
83%
**61
100%
IMR 7977 Enduron
<<locked>>
81%
47398
71%
**07
95%
IMR 8133 Enduron
<<locked>>
81%
37884
57%
**05
98%
[Lovex D100]*
<<locked>>
81%
41887
63%
**15
91%
Lovex S071
<<locked>>
81%
49327
74%
**33
100%
Norma 217
<<locked>>
81%
38812
58%
**21
99%
[Ramshot LRT]*
<<locked>>
84%
42032
63%
**03
90%
ReloadSwiss RS 14
<<locked>>
81%
30226
45%
**65
100%
ReloadSwiss RS 76
<<locked>>
81%
50314
75%
**81
100%
ReloadSwiss RS 80
<<locked>>
81%
46064
69%
**85
99%
[SNPE Vectan SP 13]*
<<locked>>
81%
32445
49%
**18
90%
[Vihtavuori 20N29]*
<<locked>>
86%
36738
55%
**43
90%
[Vihtavuori 24N41]*
<<locked>>
84%
41858
63%
**67
90%
Vihtavuori N165
<<locked>>
81%
52721
79%
**99
100%
[Vihtavuori N170]*
<<locked>>
81%
40683
61%
**92
94%
Vihtavuori N565
<<locked>>
81%
51503
77%
**54
100%
Vihtavuori N568
<<locked>>
81%
46543
70%
**89
98%
Vihtavuori N570
<<locked>>
81%
44991
67%
**92
96%

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.

bottom of page