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510910SP307 Technical Profile © Application: Target/Tactical

Barrel Bore Diameter: 0.500" 12.690 mm The diameter of the barrel from land to land.

Barrel Groove Diameter: 0.509" 12.920 mm The diameter of the barrel from groove to groove.

Bullet Weight: 910gr 59.0g Bullets are guaranteed to weigh within 0.25% of the stated weight.

Bullet Length: 2.79" 70.900 mm

Tangent Ogive Length: 1.44" 36.664 mm These dimensions are critical to consistent external ballistic performance and are held constant to within 0.005 mm (0.0002")

Meplat Diameter: 0.05" 1.269 mm

Min Bullet Protrusion: 1.54" 39.170 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: 2.05" 52.000 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: 3300fps 1 006 m/s If the maximum muzzle speed is exceeded, dynamic stabilty problems may be encountered.

Twist: Sg = 1.5: 13.0" / 332 mm 26.1 Cal. in length The twist required to give a calculated Sg 1.5

Minimum Twist: 14" / 355.6 mm 28.0 Calibers in length The twist required for stable flight and the best long range tractability more than 600 yds or 550 m. See the 'Notes' hereunder.

Calculated Ballistic Coefficient - G1 profile

BC = 1.203 Maximum to 2250 fps Maximum to 686 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 excact values, shoot drop tables at the elevation and temperature for your location.

BC = 1.103 2250 fps to 1200 fps 686 m/s to 366 m/s

BC = 0.826 1200 fps to 0 fps 366 m/s to 0 m/s

Suitable Cartridges, with consideration of the above specifications:

.510" Calibers

NOTES

A Gyroscopic Stability (Sg) greater than 1.2 is required for SP bullets. For use under 600yds/550m an Sg of up to 1.5 or even greater can be used. For distances beyond 600yds/550m, 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.

510910SP307 Technical Profile © Application: Target/Tactical

Barrel Bore Diameter:	0.500"	12.690 mm	The diameter of the barrel from land to land.
Barrel Groove Diameter:	0.509"	12.920 mm	The diameter of the barrel from groove to groove.
Bullet Weight:	910gr	59.0g	Bullets are guaranteed to weigh within 0.25% of the stated weight.
Bullet Length:	2.79"	70.900 mm
Tangent Ogive Length:	1.44"	36.664 mm	These dimensions are critical to consistent external ballistic performance and are held constant to within 0.005 mm (0.0002")
Meplat Diameter:	0.05"	1.269 mm
Min Bullet Protrusion:	1.54"	39.170 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:	2.05"	52.000 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:	3300fps	1 006 m/s	If the maximum muzzle speed is exceeded, dynamic stabilty problems may be encountered.

Twist: Sg = 1.5:	13.0" / 332 mm	26.1 Cal. in length	The twist required to give a calculated Sg 1.5
Minimum Twist:	14" / 355.6 mm	28.0 Calibers in length	The twist required for stable flight and the best long range tractability more than 600 yds or 550 m. See the 'Notes' hereunder.

Calculated Ballistic Coefficient - G1 profile
BC = 1.203	Maximum to 2250 fps	Maximum to 686 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 excact values, shoot drop tables at the elevation and temperature for your location.
BC = 1.103	2250 fps to 1200 fps	686 m/s to 366 m/s
BC = 0.826	1200 fps to 0 fps	366 m/s to 0 m/s
Suitable Cartridges, with consideration of the above specifications:

.510" Calibers


NOTES
A Gyroscopic Stability (Sg) greater than 1.2 is required for SP bullets. For use under 600yds/550m an Sg of up to 1.5 or even greater can be used. For distances beyond 600yds/550m, 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.