HOME
PRODUCTS
GALLERY
THEY SAY
CONTACT US

257100HV054 Technical Profile

Bore Diameter:

0.250"

6.350 mm

The diameter of the barrel from land to land.

Groove Diameter:

0.257"

6.530 mm

The diameter of the barrel from groove to groove.

Bullet Weight:

100gr

6.5g

Bullets are guaranteed to weigh within 0.25% of the stated weight.

Bullet Length:

1.28"

32.400 mm

Ogive Length:

0.71"

18.125 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 Protrusion:

0.79"

19.980 mm

Add the case length to these numbers to determine the maximum and minimum cartridge overall length that is possible with this bullet.

Max Protrusion:

1.02"

26.000 mm

Bullet does not conform to CIP and SAAMI for magazine length.

Check the magazine length of your rifle for suitability with this bullet.

Max Launch Speed:

4000fps

1,219 m/s

If the launch speed is exceeded, dynamic stabilty problems may be encountered

Minimum Twist:

9"

36.0 Cal

The twist required for stable flight and good long range terminal performance.

Sg = 1.5:

Twist = 7.8

Twist = 31.3 Cal

General hunting twist requirement. 

Short Range Twist:

7" or tighter

28.7 Cal or tighter

Twist requirement if hunting distances do not exceed 150 meters.

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 = 0.489

4000 fps to 2800 fps

1,219 m/s to 853 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.

BC = 0.427

2800 fps to 1600 fps

853 m/s to 488 m/s

BC = 0.415

1600 fps to 0 fps

488 m/s to 0 m/s

Suitable Cartridges, with consideration of the above specifications:

25-06, 257 Weatherby and other suitable cartridges