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308177HV079 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: 177gr 11.5g Bullets are guaranteed to weigh within 0.25% of the stated weight.

Bullet Length: 1.54" 39.200 mm

Tangent Ogive Length: 0.94" 23.850 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: 1.02" 25.910 mm Add the case length to these numbers to determine the maximum and minimum cartridge overall length that is possible with this bullet.

Max Bullet Protrusion: 1.22" 31.000 mm

Bullet conforms to CIP and SAAMI for magazine length. Check the magazine length of your rifle for suitability with this bullet.

Maximum M/V: 4800fps 1 463 m/s If the maximum muzzle speed is exceeded, dynamic stabilty problems may be encountered.

Short Range Twist: 8.0" / 204 mm or tighter 26.8 Cal/length or tighter Twist recommended if average hunting distances are 270 yards or 250 m. A tighter twist can be used.

Twist: Sg = 1.5: 9.0" / 226 mm 29.7 Cal. in length General hunting twist for average distances to 550 yards or 510 m. A tighter twist can be used.

Minimum Twist: 10" / 254 mm 33.3 Calibers in length The twist required for stable flight and good terminal performance further than 550 yds or 510 m.

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

Calculated Ballistic Coefficient - G1 profile

BC = 0.700 Maximum to 3200 fps Maximum to 975 m/s BC values are calculated at standard Metro values using a G1 profile. Any comparison with the BC values of other manufacturers is not valid as there is currently no standard method in use between manufacturers. Enter these values into an external ballistics program to calculate BC for your launch speed and distance. For exact values, shoot drop tables at the elevation and temperature for your location.

BC = 0.564 3200 fps to 1600 fps 975 m/s to 488 m/s

BC = 0.507 1600 fps to 0 fps 488 m/s to 0 m/s

Suitable Cartridges, with consideration of the above specifications:

.308" calibers subject to specification.

NOTES

A Gyroscopic Stability (Sg) greater than 1.1 is required for stable flight with HV and HP bullets. For hunting at average 550yds/510m, an Sg of up to 1.5 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.

308177HV079 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:	177gr	11.5g	Bullets are guaranteed to weigh within 0.25% of the stated weight.
Bullet Length:	1.54"	39.200 mm
Tangent Ogive Length:	0.94"	23.850 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:	1.02"	25.910 mm	Add the case length to these numbers to determine the maximum and minimum cartridge overall length that is possible with this bullet.
Max Bullet Protrusion:	1.22"	31.000 mm
Bullet conforms to CIP and SAAMI for magazine length.			Check the magazine length of your rifle for suitability with this bullet.
Maximum M/V:	4800fps	1 463 m/s	If the maximum muzzle speed is exceeded, dynamic stabilty problems may be encountered.
Short Range Twist:	8.0" / 204 mm or tighter	26.8 Cal/length or tighter	Twist recommended if average hunting distances are 270 yards or 250 m. A tighter twist can be used.
Twist: Sg = 1.5:	9.0" / 226 mm	29.7 Cal. in length	General hunting twist for average distances to 550 yards or 510 m. A tighter twist can be used.
Minimum Twist:	10" / 254 mm	33.3 Calibers in length	The twist required for stable flight and good terminal performance further than 550 yds or 510 m.
Minimum Impact Speed:	1600fps	488 m/s	At this impact speed, the bullet will open to at least double caliber.
Calculated Ballistic Coefficient - G1 profile
BC = 0.700	Maximum to 3200 fps	Maximum to 975 m/s	BC values are calculated at standard Metro values using a G1 profile. Any comparison with the BC values of other manufacturers is not valid as there is currently no standard method in use between manufacturers. Enter these values into an external ballistics program to calculate BC for your launch speed and distance. For exact values, shoot drop tables at the elevation and temperature for your location.
BC = 0.564	3200 fps to 1600 fps	975 m/s to 488 m/s
BC = 0.507	1600 fps to 0 fps	488 m/s to 0 m/s
Suitable Cartridges, with consideration of the above specifications:

.308" calibers subject to specification.


NOTES
A Gyroscopic Stability (Sg) greater than 1.1 is required for stable flight with HV and HP bullets. For hunting at average 550yds/510m, an Sg of up to 1.5 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.