Sierra .243 caliber 107 grain MatchKing

Dimensions taken from Lot#003842744

Sample Size:

10

Ogive Radius:

11.32 calibers

Sectional Density:

0.259lb/in2

Rt/R:

0.89

  This well designed target bullet from Sierra has been used reliably in many medium to high capacity 6mm chamberings for many years.  In this caliber, the 115 grain bullets are the heaviest options available, but often times those longer bullets come with their own problems related to reliable consistency, fouling, etc.  At 107 grains, this bullet is heavy enough to have a respectably high BC while not being excessively long and incurring those problems.

  As the stability data indicates, this bullet is comfortably stable in a 1:8" twist in all but the worse case conditions, and even then the stability factor is still 1.33 which would result in acceptably accurate flight.

  This bullet is the 'middle brother' in the heavy end of Sierras 6mm target bullet line-up.  The 95 grain and the 115 grain bullets have essentially the same nose and tail, and almost identical form factors as a result.  The only difference being the weight which is taken up in the bearing surface.

  Depending on your cartridge and muzzle velocity, this bullet can achieve good ballistic performance in most any mid-range and some long range shooting applications.  Although probably a little smaller than optimal for 1000 yard competition, it does have plenty of performance for 600 and in.

Drag and Ballistic Coefficient

Fps/Mach

Cd

i7

G7 BC

i1

G1 BC

1500/1.34

0.364

0.991

0.259

0.551

0.466

2000/1.79

0.315

1.005

0.255

0.506

0.508

2500/2.23

0.282

0.991

0.259

0.498

0.516

3000/2.68

0.257

0.989

0.260

0.485

0.529

Average:

0.994

0.258

0.510

0.505

Variation:

0.016

0.004

0.066

0.063

Rifling Twist Rate and Stability

Stability Factor

Barrel Twist

Best case

Nominal

Worst Case

1:7”

2.31

2.02

1.74

1:8”

1.77

1.54

1.33

1:9”

1.40

1.22

1.05

1:10”

1.13

0.99

0.85

*Stability Factor above 1.4 indicates good stability.  Below 1.4 indicates marginal stability.  Less than 1.0 is unstable.