THE HANDLOADING BENCH
308 Winchester Rides Again Part 4 By Laurie Holland
Seating dummy for the 155gn BJD-HBC VLD for the old barrel alongside that for the 208gn A-Max in its succes- sor. Despite a 120-130 thou’ jump to the leade six rounds of leftover ammo shot a 0.4-MOA group.
The seating dummy on the right shows the COAL used for the 208gn A-Max in the more generously throated 2012 barrel and is much better suited to these bullets. 2010/11 barrel version
alongside.despite testing in cool conditions.
As you see in the photograph, four out of five 200- 210gn bullets tried were seated at least an eighth to tenth inch deeper than is desirable. The 210gn Berger BT Long-Range was the only one whose base was on the case shoulder to body junction. The newly fitted barrel has the longer-throat multi-purpose #2 form, again employing 1-10.
When talking about rifling twist rates, not every barrel maker provides the full range. Bartlein will supply a twist to your specification to two decimal places but you’ll likely wait even longer than the normal six to eight months delivery time if you really must have 1-11.66 or suchlike! True-Flite offers 30 calibre blanks in 12, 13, or 14 rates (tight-bore); 8, 10, and 12 (standard bore dimensions) only.
Heavy Metal I tried seven heavy bullet models during 2010/11 –
primarily Berger’s two 210s (BT and VLD); Sierra’s old 200-grainer; Hornady’s 208gn A-Max. (The new Berger Hybrid models in 200, 215 and 230gn weights and the heavy Hornady HPBT models had yet to appear.)
According to Bryan Litz, the A-Max has the highest BC of this bunch at 0.323, only marginally above that of the Bergers. Unusually, the Berger VLD and BT Long- Range have near identical G7 BCs of 0.320 and 0.321, the A-max so close to these values that Bryan would readily concede these small differences fall within the accuracy tolerances of his experimentally based measuring method. (You can increase the two Berger hollow-point designs’ BCs a little further by use of a ‘pointing’ die, gaining another 2 or 3% to edge them up to the .330 mark, an option not available with the plastic tipped A-Max.) The 210gn Sierra also scores close to the others with 0.316, so we can say that in terms of simple external ballistics abilities, there is no ‘winner’ here.
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