Sierra .264 cal 142 grain MatchKing

Dimensions taken from Lot#0039855964848

Sample Size:

10

Ogive Radius:

11.1  calibers

Sectional Density:

0.291 lb/in2

Rt/R:

0.84

  This bullet has become a benchmark for all disciplines of long range target shooting over the last 10-15 years.  When fired from the 6.5-284 at around 2950-3000 fps, the ballistic performance, accuracy, and low recoil are simply difficult to beat without giving something up (for example, better ballistics means substantially more recoil).  

    It’s no surprise that this bullet has achieved such wide success; the design is very difficult to improve on.  Starting with the long ogive which minimizes wave drag.  An Rt/R ratio of .84 is conducive to low drag without making the bullet highly sensitive to seating depth.  Even though it’s a heavy bullet for the caliber, the bearing surface isn’t so long that it causes excessive copper fouling (although barrel life for the 6.5-284 is known to be short with any bullet).  Finally the long 7 degree boat tail is optimal for minimizing base drag.

    There is a very long list of match and tournament wins in Long Range Benchrest, F-class, and Prone disciplines that are attributable to this bullet.

    Unfortunately in recent times (since around 2010) many shooters have noticed that the quality control at Sierra isn’t what it once was.  Many of their MatchKing bullets require sorting into batches of similar dimensions in order to shoot well.  Lots of shooters have switched to one of the many 140 grain options available from other bullet makers to replace this bullet. Current events aside, there is no doubt that this has been one of the most successful long range target bullets ever made.

Drag and Ballistic Coefficient

Fps/Mach

Cd

i7

G7 BC

i1

G1 BC

1500/1.34

0.354

0.963

0.302

0.535

0.544

2000/1.79

0.307

0.978

0.298

0.492

0.591

2500/2.23

0.275

0.966

0.301

0.485

0.600

3000/2.68

0.251

0.965

0.302

0.473

0.615

Average:

0.968

0.301

0.496

0.588

Variation:

0.015

0.005

0.062

0.072

Rifling Twist Rate and Stability

Stability Factor

Barrel Twist

Best case

Nominal

Worst Case

1:8"

1.97

1.72

1.49

1:9"

1.56

1.36

1.18

1:10"

1.26

1.10

0.95

1:11"

1.04

0.91

0.79

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