THE HANDLOADING BENCH
308 Winchester Rides Again Part 4 By Laurie Holland
What we’re trying to avoid by using heavy, high-BC bullets – a bullet blown to the right barely in the ‘Three-ring’ by a wind change. The competitor’s elevation isn’t too hot either being a full MOA high!
Potentially suitable powders for ‘heavies’ in .308 Winchester. Newly arrived Elcho 17 is identical to Reloder 17 but much cheaper.
Many readers will wonder about Elcho 17. It’s the Swiss double-base extruded powder manufactured by Nitro-Chemie AG and packaged as Reloder 17 by Alliant ATK in the USA. A British importer buys it in bulk from the makers and packages it in 1kg tubs as Elcho 17. Alliant Re17 loading data can be used with it. Its recommended retail price is a bargain £55 / Kg. (£24.95 / lb) ‘Elcho’ refers to the famous 150 year old Elcho Shield Match Rifle 1000 to 1200 yard competition that is shot at Bisley each summer between 8-shooter teams from England, Republic of Ireland, Scotland, and Wales.
Do a QuickLOAD Propellant Table Run and you find there are other powders that are capable of producing high velocities allied to a near 100% charge burn. Table 2 lists a dozen powders that are available in the UK and which produce a calculated MV of 2,550 fps or above with the 210gn Berger BTLR in a suitably throated 30 inch barrel.
Producing good velocities is not the same thing as producing a good load of course. Few long-range shooters will use relatively dirty burning ball powders for instance, ruling H414/W760, H. BL-C(2), H380 out
straight away. I concentrated on Viht N550 and Alliant Reloder 17 in my tests as they have proven track records but also loaded a small number of batches over IMR-4007ssc, Hodgdon VarGet, and Hodgdon H414.
As with so many other .308 Win applications, VarGet is a firm favourite with American F/TR shooters. It not only gives a good all-round performance with this class of bullet, but is temperature tolerant, an important consideration to our American friends. We don’t worry much about this in the British Isles given our ‘temperate’ (cold!) climate but hot-shot powders that produce tiny groups, good velocities and small spreads at 60-70F are no good to Americans if they see group dispersion double, likewise velocity spreads and, worst of all, produce serious over-pressures when the mercury hits 90. My sole run with the powder produced higher velocities than QuickLOAD suggested.
Ask our GB top F/TR heavy-users what brass they use and there is a near unified response – the Lapua ‘Palma’ match case. The exception to the rule is George Barnard who runs Norma cases with 210s.
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