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308189HV309 Technical Profile © Application: Long Range Hunting

Barrel Bore Diameter: 0.300" 7.620 mm The diameter of the barrel from land to land.

Barrel Groove Diameter: 0.308" 7.820 mm The diameter of the barrel from groove to groove.

Bullet Weight: 189gr 12.3g Bullets are guaranteed to weigh within 0.25% of the stated weight.

Bullet Length: 1.63" 41.500 mm

Tangent Ogive Length: 1.03" 26.126 mm These dimensions are critical to consistent external ballistic performance and are held constant to within 0.005 mm (0.0002")

Meplat Diameter: 0.06" 1.650 mm

Min Bullet Protrusion: 1.11" 28.190 mm Add the case length to these numbers to determine the maximum and minimum cartridge overall length (COL) that is possible with this bullet.

Max Bullet Protrusion: 1.38" 35.000 mm

CIP and SAAMI cartridge overall length (COL) not observed or does not apply. Check the COL of your rifle for suitability with this bullet as described above.

Maximum M/V: 4000fps 1 219 m/s If the maximum muzzle speed is exceeded, dynamic stabilty problems may be encountered.

Minimum Impact Speed: 1600fps to 1700fps 488 m/s to 518 m/s At this impact speed, the bullet will open to at least double caliber.

Twist Rates are guidelines but the Minimum Twist must be observed

Twist: Sg = 1.4: 8.5" / 217 mm or tighter 28.4 Calibers or tighter General hunting twist for average distances to 590 yards or 540 m. A tighter twist (smaller number) can be used.

Minimum Twist: 9.5" / 241.3 mm 31.7 Calibers The slowest twist required for stable flight and good terminal performance further than 880 yds or 810 m. See 'Notes' below.

Calculated Ballistic Coefficient - Standard Metro G1 profile

BC = 0.681 Maximum M/V to 2800 fps Maximum M/V to 853 m/s Any comparison with the BC values of other manufacturers is not valid as there is currently no standard method in use between manufacturers. These BC values are only for use in an external ballistics program. Use the three values, as given, to approximately calculate BC for your launch speed and distance. For exact numbers, shoot drop tables at the elevation and temperature for your location.

BC = 0.578 2800 fps to 1600 fps 853 m/s to 488 m/s

BC = 0.545 1600 fps to 0 fps 488 m/s to 0 m/s

Suitable Cartridges, with consideration of the above specifications:

.308" Cartridges

NOTES

A Gyroscopic Stability (Sg) greater than 1.1 is required for stable flight with HV and HP bullets. For hunting under 590yds/540m, an Sg of up to 1.4 or more can be used. For longer distances the Sg can be decreased but never less than 1.1.

*Note that Sg increases as twist tightens. *A 1:10" twist is tighter than a 1:12" twist within a given caliber only. *Twist rates given in caliber lengths can be compared across calibers. *Choose a bullet length best suited to your rifle twist and type of shooting. *When a bullet is specified for a given twist rate, it can also be used in any twist that is tighter. Using it in a slower twist than specified, is not advisable. *Some experimentation will be required to determine exact drop tables for your equipment and location.

308189HV309 Technical Profile © Application: Long Range Hunting

Barrel Bore Diameter:	0.300"	7.620 mm	The diameter of the barrel from land to land.
Barrel Groove Diameter:	0.308"	7.820 mm	The diameter of the barrel from groove to groove.
Bullet Weight:	189gr	12.3g	Bullets are guaranteed to weigh within 0.25% of the stated weight.
Bullet Length:	1.63"	41.500 mm
Tangent Ogive Length:	1.03"	26.126 mm	These dimensions are critical to consistent external ballistic performance and are held constant to within 0.005 mm (0.0002")
Meplat Diameter:	0.06"	1.650 mm
Min Bullet Protrusion:	1.11"	28.190 mm	Add the case length to these numbers to determine the maximum and minimum cartridge overall length (COL) that is possible with this bullet.
Max Bullet Protrusion:	1.38"	35.000 mm
CIP and SAAMI cartridge overall length (COL) not observed or does not apply. Check the COL of your rifle for suitability with this bullet as described above.
Maximum M/V:	4000fps	1 219 m/s	If the maximum muzzle speed is exceeded, dynamic stabilty problems may be encountered.
Minimum Impact Speed:	1600fps to 1700fps	488 m/s to 518 m/s	At this impact speed, the bullet will open to at least double caliber.
Twist Rates are guidelines but the Minimum Twist must be observed
Twist: Sg = 1.4:	8.5" / 217 mm or tighter	28.4 Calibers or tighter	General hunting twist for average distances to 590 yards or 540 m. A tighter twist (smaller number) can be used.
Minimum Twist:	9.5" / 241.3 mm	31.7 Calibers	The slowest twist required for stable flight and good terminal performance further than 880 yds or 810 m. See 'Notes' below.
Calculated Ballistic Coefficient - Standard Metro G1 profile
BC = 0.681	Maximum M/V to 2800 fps	Maximum M/V to 853 m/s	Any comparison with the BC values of other manufacturers is not valid as there is currently no standard method in use between manufacturers. These BC values are only for use in an external ballistics program. Use the three values, as given, to approximately calculate BC for your launch speed and distance. For exact numbers, shoot drop tables at the elevation and temperature for your location.
BC = 0.578	2800 fps to 1600 fps	853 m/s to 488 m/s
BC = 0.545	1600 fps to 0 fps	488 m/s to 0 m/s
Suitable Cartridges, with consideration of the above specifications:

.308" Cartridges


NOTES
A Gyroscopic Stability (Sg) greater than 1.1 is required for stable flight with HV and HP bullets. For hunting under 590yds/540m, an Sg of up to 1.4 or more can be used. For longer distances the Sg can be decreased but never less than 1.1.

Note that Sg increases as twist tightens. A 1:10" twist is tighter than a 1:12" twist within a given caliber only. Twist rates given in caliber lengths can be compared across calibers. Choose a bullet length best suited to your rifle twist and type of shooting. When a bullet is specified for a given twist rate, it can also be used in any twist that is tighter. Using it in a slower twist than specified, is not advisable. Some experimentation will be required to determine exact drop tables for your equipment and location.