318157HV123 Technical Profile © Application: General Hunting

Barrel Bore Diameter: 0.307" 7.800 mm The diameter of the barrel from land to land.
Barrel Groove Diameter: 0.318" 8.070 mm The diameter of the barrel from groove to groove.
Bullet Weight: 157gr 10.2g Bullets are guaranteed to weigh within a quarter percent of the stated weight.
Bullet Length: 1.27" 32.200 mm
Tangent Ogive Length: 0.71" 18.000 mm These dimensions are critical to consistent external ballistic performance and are held constant to within 0.005 mm (0.0002")
Meplat Diameter: 0.09" 2.200 mm
Min Bullet Protrusion: 0.81" 20.630 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: 0.94" 24.000 mm
Bullet conforms to CIP and SAAMI for magazine length. Case and COL based on: 8x57J. Check the COL of your rifle for suitability with this bullet as described above. Check the magazine length of your rifle for suitability with this bullet.
Maximum M/V: 3600fps 1,097 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: 11.3" / 287 mm 36.8 Calibers General hunting twist for average distances to 440 yards or 410 m. A tighter twist (smaller number) can be used.
Minimum Twist: 12.25" / 311.15 mm 39.9 Calibers The slowest twist required for stable flight and good terminal performance further than 440 yds or 410 m. See 'Notes' below.

Calculated Ballistic Coefficient - Standard Metro G1 profile. Based on: Cd = 0.279

BC = 0.392 Maximum M/V to 2600 fps Maximum M/V to 792 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 = 0.363 2600 fps to 1600 fps 792 m/s to 488 m/s
BC = 0.363 1600 fps to 0 fps 488 m/s to 0 m/s

Suitable Cartridges, with consideration of the above specifications:

8X57J, Use the specification sheet above to determine whether this bullet is suitable for the cartridge.

NOTES

A Gyroscopic Stability (Sg) greater than 1.1 is required for stable flight with HV and HP bullets. For hunting under 440yds/410m, 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.