224057SP209 Technical Profile ©   Application: Target/Tactical

Barrel Bore Diameter: 0.219" 5.560 mm The diameter of the barrel from land to land.
Barrel Groove Diameter: 0.224" 5.690 mm The diameter of the barrel from groove to groove.
Bullet Weight: 58gr 3.8g Bullets are guaranteed to weigh within 0.25% of the stated weight.
Bullet Length: 0.84" 21.300 mm
Tangent Ogive Length: 0.37" 9.472 mm These dimensions are critical to consistent external ballistic performance and are held constant to within 0.005 mm (0.0002")
Meplat Diameter: 0.02" 0.556 mm
Min Bullet Protrusion: 0.43" 10.890 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: 0.71" 18.000 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: 4000fps 1,219 m/s If the maximum muzzle speed is exceeded, dynamic stabilty problems may be encountered.
       
Twist: Sg = 1.5: 9.0" / 232 mm 41.7 Cal. in length The twist required to give a calculated Sg 1.5
Minimum Twist: 10" / 254 mm 45.7 Calibers in length The twist required for stable flight and the best long range tractability more than 410 yds or 380 m.
       
Calculated Ballistic Coefficient - G1 profile  
BC = 0.253 4000 fps to 2600 fps 1,219 m/s to 792 m/s BC values are calculated at standard Metro values and serve as a comparison between GSC bullets.  Any comparison with the BC values of other manufacturers is not valid as there is currently no standard method in use between manufacturers.
BC = 0.216 2600 fps to 1200 fps 792 m/s to 366 m/s
BC = 0.159 1200 fps to 0 fps 366 m/s to 0 m/s

Suitable Cartridges, with consideration of the above specifications:

222 Rem, 222 Rem Mag, 223 Rem, 22-250, 5.6x57, 5.6x61 SE.v.H,

NOTES

A Gyroscopic Stability (Sg) greater than 1.2 is required for SP bullets. For use under 410yds/380m an Sg of up to 1.5 or even greater can be used. For distances beyond 410yds/380m, the Sg can be decreased with a slower twist, but never less than 1.2 for GSC SP bullets.
*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.