Following 3-round group-tests designed to get a feel for how these combinations performed, I ran five by 5-round grouping trials side by side on yet another miserable, wet and chilly late June day, temperatures struggling to break 10°C / 50F. ‘Palma charges’ ran higher than those used in standard brass to give equivalent MVs, the charge weight range being 48.4 to 49.2gn x 0.2gn steps in standard LRP Lapua cases; 48.9 to 49.9gn x 0.3gn followed by 0.2gn steps in SRP ‘Palma’ cases. CCI-BR4 primers were again used in the latter, but due to accident not design, I grabbed a box of LRP brass primed with CCI-200s instead of the F210M match type used in other comparisons. I really expected the ‘Palma’ loads to struggle with this powder in the conditions especially with charges nudging 50-grains, but this wasn’t how things worked out. The five LRP groups covered a poor 0.6” to 1.25” and MVs plateaued over a 0.6gn charge weight range, 48.8 to 49.2gn producing 2,855 to 2,860 fps. ‘Palma loads’ grouped between 0.4” and 0.8” and MVs rose in line with charges ending up at 2,877 fps. So far as velocity spreads went, neither case gave great results with this powder, but the ‘Palma’ case again came out the
THE HANDLOADING BENCH
308 Winchester Rides Again Part 3 By Laurie Holland
Heavies Let’s move onto heavy bullets in the cartridge,
especially in the F/TR role where an 18lb rifle and bi-pod support can cope with recoil and torque levels that would be unacceptable to sling shooters, also those in tactical, McQueens, or service rifle disciplines with their need for minimal sight-disturbance and quick follow-up shots. First of all, what is a heavy
Old and new ‘heavies’. Left to right: 155gn Sierra MK (for comparison); 190gn SMK; 200gn SMK; 208gn A-Max; 210gn Berger BTLR; 210gn Berger VLD; 210gn SMK. Note the short blunt nose sections and long boat-tails on the two older SMKs compared to the more modern bullets. Sierra’s 210 on the extreme right is a VLD design and very different from its geriatric stablemates.
winner with a range of 17-31 fps over the five batches averaging 23 fps; the LRP loads ran between 19 and 50 fps for an average of 29 fps. Both produced the characteristic ball powder hard fouling on outside neck surfaces that took a lot of cleaning when I came to reload the cases. Incidentally, there is a claimed method of alleviating this problem – spray the fouling with WD40, better still that unique German coal based oil, Ballistol immediately after shooting, wait 10 minutes and wipe the softened muck off with a paper towel. I must try this trick one day, although it could prove rather difficult logistically in a match.
bullet in .308? Many TR shooters reckon anything above 155gn is ‘heavy’, while Bryan Litz of Berger Bullets argues that 230gn is the .30-calibre equivalent of the 140s routinely used in 6.5mm and 180s in 7mm. I’ve arbitrarily set 190gn as my floor for this exercise. On this definition, we’ve 14 bullets from three manufacturers (Berger, Hornady, and Sierra) available in the UK at the time of writing, although I expect Fox Firearms UK to have some more from a fourth maker (Swampworks / JLK) available by the time you read this. Table 1 lists their key ballistic statistics, predicted 1,000 yard performance, and the rifling twist rate that produces an Sg (stability factor) value of 1.4 at their expected MVs. Four of the 14 are elderly: Sierra’s 190,
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