THE HANDLOADING BENCH
308 Winchester Rides Again Part 3 By Laurie Holland
range of speeds and conditions.
Cons Well, we’ve seen the ‘pros’ and they’re all related to
predicted long-range external ballistics performance. Everybody will have switched to the more efficient ‘heavies’ surely? ..... but, no. if you revisit the report on the F Class European Championship meeting in the December issue of TS Online, you’ll see a table listing what kit and loads were used by the top 10 F/ TR shooters. Runaway winner Stuart Anselm used an intermediate weight model, the 185gn Berger BTLR; four used 210gn ‘heavies’, another four loaded Berger 155.5s, and the final odd-man out (sole non Berger user) shot the Australian 155gn BJD-HBC. However, the winds weren’t very strong over that weekend – if an early winter weather depression with 20 mph plus winds had blown in, ‘heavies’ users might have outnumbered the 155gn brigade in the top spots.
Let’s look at the ‘cons’, and the overwhelming downsides are an increase in recoil and torque. Increasing the bullet weight from 155 to 210gn increases recoil energy by over 20% in an 18lb F/TR rifle, from 8.7 to 10.6 ft/lbs. That might not sound much, but it will affect rifle handling and bi-pod movement on the ground. I notice that some of the
more successful heavy bullet shooters have fitted spikes to the bi-pod feet allowing them to ‘load the bi-pod’, that is lock the foot position and put the legs under tension to reduce movement and eliminate the dreaded bi-pod leap in the air that not only affects shot to shot consistency, but can see you unknowingly lined up on the neighbouring target for the next shot with the consequent risk of cross-shooting and a guaranteed loss of five points. A heavier bullet also puts more stress on every major component in the rifle from the barrel through the receiver and bolt to the bedding. In my look at the ‘pros’, there was the proviso that ‘heavies’ will produce the same size groups as 155s, but there is a lot of evidence that while it’s possible to achieve this, it’s very hard to do so. For whatever reason or reasons, most heavy bullet shooters say their long-range ‘elevations’ are bigger than they expect from a good 155gn bullet load, and this is the ‘swing’ you lose on against the gains from the reduced wind drift ‘roundabout’. High energy double-base powders are de rigueur in the 308’s constrained capacity case to get full velocities from these bullets, and this allied to greater bullet inertia will see throat erosion and damage set in quicker, so barrel life will be reduced, likely to 2,000-2,500 rounds.
Next month: twist rates, chamber throat lengths, powders, loads and 200-210gn bullet results to finish things off.
Table 1 External Ballistic Performance from Heavy 0.308” Match Bullets
Bullet 155.5 BT FB
190gn Sierra MK 190gn Berger VLD 200gn Sierra MK
200gn Berger Hybrid 208gn Hornady A-Max 210gn Berger VLD 210gn Berger BTLR 210gn Sierra MK
215gn Berger Hybrid 220gn Sierra MK
230gn Berger Hybrid i7 BC V0 (fps)
0.988 0.237 3,000 1.070 0.268 2,714 0.982 0.291 2,714 1.058 0.285 2,645 0.944 0.320 2,645 0.966 0.324 2,594 0.985 0.321 2,582 0.988 0.320 2,582 1.000 0.316 2,582 0.910 0.356 2,551 1.068 0.310 2,522 0.911 0.380 2,467
Twist V1,000 (fps) 12.5” 1,304 (1.16 M) 12.1” 1,269 (1.13 M) 11.7” 1,364 (1.21 M) 11.9” 1,292 (1.15 M) 10.6” 1,417 (1.26 M) 10.5” 1,393 (1.24 M) 11”
1,375 (1.22 M)
11.25” 1,371 (1.22 M) 11.1” 1,359 (1.21 M) 10.3” 1,454 (1.29 M) 11.2” 1,296 (1.15 M) 10”
1,450 (1.19 M)
D1,000 (MOA / Inches) 8.7 / 91” 8.6 / 90” 7.6 / 80” 8.2 / 86” 7.0 / 73” 7.1 / 74” 7.2 / 76” 7.3 / 76” 7.4 / 77” 6.4 / 67” 7.9 / 83” 6.2 / 65”
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